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# Why objects float or sink when placed on the surface of water

1. If the density of the object is less than or equal to the density of the liquid, then it floats on the surface of the liquid. This is because the buoyant force acting on the object is equal to the weight of the object. Answer verified by Toppr Upvote (0
2. Now, whether an object will float or sink in water will depend on the relative magnitudes of these two forces (weight and buoyant force) acting on the object in opposite directions. If the buoyant force (or upthrust) exerted by water is equal to or greater than the weight of the object, will float in water
3. An object will float on the surface of water when it has density less than that of water because it always displaces more weight of water than its own weight, and as the buoyant force is more than its own weight, therefore it floats
4. Write the formula to find the magnitude of the gravitational force between the Earth and an object on the surface of the Earth. asked Apr 27, 2020 in Physics by Bhuvan01 ( 68.4k points) class-
5. Different objects float at different levels in the water because as most regular objects are lowered into the surface of water, the upward push of the water steadily increases until it is in balance with the weight force of the object, and the object then continues floating at this level with the two forces in balance
6. In this Science (Physics) video in Hindi for Class 9 we explained why objects float or sink when placed on the surface of water. This is a topic from Chapter..
7. Objects with tightly packed molecules are more dense than those where the molecules are spread out. Density plays a part in why some things float and some sink. Objects that are more dense than water sink and those less dense float. Hollow things often float too as air is less dense than water

### Floating and sinkin

• Why do things float in water? When an object is placed in a fluid, the fluid presses on the object in all directions. Whether an object sinks or float in a liquid depends mainly on two factors: The diagram shows the bowling ball on the bottom of the container of water. Density plays a part in why some things float and some sink
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• Hey samadhan, An object may float or sink when placed on the surface of water because of the principle of buoyancy. Which is quite simply the upward force that is exerted on an object by the fluid on whose surface the object is placed. Let's take a very simple example of a paper boat placed on a water
• Things float or sink bcz of its density. If the density of the body is less than the density of the liquid in which it is placed so it floats on that liquid. For example a piece of cork floats on water bcz its density is less than the density of water
• WHY OBJECTS FLOAT OR SINK WHEN PLACED ON THE SURFACE OF WATER? By PrashantYogananda | Updated: Feb. 21, 2016, 2:24 p.m. Loading... Slideshow Movie. At the moment Powtoon presentations are unable to play on devices that don't support Flash
• When more of the surface is touching the water, the object is more buoyant (BOY-ant), which means it floats better. When an object floats, it pushes water out of the way

If the water weight that is displaced is less than the object's total weight, the object sinks. People are often confused how a chunk of steel, which sinks if thrown into water, can be formed into a ship that floats. The answer lies in the shape of the object » An object that floats stays above the surface of the water. » Weight is one factor in sinking and floating, but it is not the cause. Some children may think an object sinks or floats because an object is heavy or light. But not all heavy objects sink, and not all light objects float

### Why objects float or sink when placed on the surface of

The objects sinking or floating in water depends on the density of the object. If the object has more density than water then it will sink in water. Example of such objects is- rock, marble, steel, iron, copper, nickel, gallium, sand, beryllium and mercury surface of the water. - Does it sink or float? 2. Now place the middle sized sphere on the surface of the water - Does it sink or float? Your results might change if you are really careful placing the sphere 3. Now predict whether the smallest sphere will sink or float. - Where you right? Is this cube sensitive to how you place it on the surface Solid objects are generally less compressible, so if we place a solid object in a liquid it will sink to a level where its (constant, incompressible) density is equal to the (gradually increasing) density of the liquid, and it will float there Float or Sink? The density of water is 1 g/ml or 1 kg/L or 1000 kg/m3 • If an object has a density less than that of water, it will float. • If an object has a density more than that of water, it will sink. But WHY?.. Why does an object float or sink when placed on the surface of water? Answer: The density of the objects and water decides the floating or sinking of the object in water. The density of water is 1 gm/cm3. If the density of an object is less than the density of water then the object will float

Class 9th Physics - GRAVITATION - Why do objects float or sink Watch more videos at https://www.tutorialspoint.com/videotutorials/index.htm Lecture By: Ms. P.. 3. Why does an object float or sink when placed on the surface of water? Answer. An object floats on the surface of water when its density is less than that of water. This is because the upthrust acting on it is greater than the force of gravity. However, if the density of the object is greater than that of water, then the object will sink as. Hypothesis: I think that the density of the object will make it either float/sink Equipment: Rolling pin,Wooden spoon,ice-block stick,Candle (3 sizes),& water Method: Put an object in 1 by 1, leave it for a few mins Results: Wood: All the sizes of wood floated. Candle:All the sizes of candles also floated. 29 If the weight of the object is greater than the upthrust, then the object sinks. The object cannot displace enough fluid to counteract its own weight, so it sinks. and as a consequence, if the object has a greater density than the fluid, the object sinks. This is why a solid steel object (density ~8000kg/m 3) like a fork, will sink in water A rock put under water also pushes a lot of water out of the way. That water would weigh less than the rock, so the rock will sink. However, ocean water mass or saltwater mass is heavier because the ocean water has the mass of pure water, as well as the mass of the salt, so things are more likely to float on saltwater than pure water

heavy objects sink and light objects float regardless of their size, shape or the type of material used to make them. a true floating object must be wholly above the surface of the liquid. all objects that float must contain some trapped air and that is the only reason why they float. the amount of liquid on which the object floats matters. SolutionShow Solution. If the density of an object is more than the density of the liquid, then it sinks in the liquid. This is because the buoyant force acting on the object is less than the force of gravity. On the other hand, if the density of the object is less than the density of the liquid, then it floats on the surface of the liquid

At the root of the Cheerio Effect are buoyancy, surface tension, gravity, and the meniscus effect—basic physics concepts. Buoyancy or density of an object compared to the water or air surrounding it, determines whether an object submerged in water or surrounded by air will sink, float, or stay put. Buoyancy is what keeps objects afloat The buoyant force is always present whether the object floats, sinks, or is suspended in a fluid. Archimedes' principle states that the buoyant force on an object equals the weight of the fluid it displaces. Specific gravity is the ratio of the density of an object to a fluid (usually water) Objects sink into water until the weight of water displaced is equal to the weight of the object. If the water weight that is displaced is less than the object's total weight, the object sinks. People are often confused how a chunk of steel, which sinks if thrown into water, can be formed into a ship that floats An object in a fluid is displacing some of the fluid. The upthrust force is equal in size to the weight of the fluid displaced by the object. Floating and sinkin Use the Activity Sheet to say whether you think each object will sink or float. Place the objects in the water one at a time to see if they sink or float. Write down your results on the Activity Sheet. Expected results: Objects that sink: Penny Paper clip Eraser Rubber band. Objects that float: Candle Crayon Pencil Popsicle stick. Ask student

It almost can float on water. Let me explain. The buoyant force experienced by an object is given by the Archimedes principle: [math]F_{buoyant}=weight of water displaced by the object[/math] Now this force [math]F_{buoyant}[/math] must balance ou.. expains why ab object placed in a fluid will either float or sink. the pressure exerted on an object by a fluid is always ____ to the surface of the object. perpindicular. the buoyant force ____ on the shape of the object in the fluid. depends. as an object sinks deeper into a fluid, the buoyant force on it _____ remains the same Floating a needle: A carefully placed small needle can be made to float on the surface of water even though it is several times as dense as water. If the surface is agitated to break up the surface tension, then needle will quickly sink. Don't touch the tent!: Common tent materials are somewhat rainproof in that the surface tension of water. In other words, it will float. If its volume is less than 25.2 cm 3, it will not stop before its entire volume sinks below the surface. p>Whether an object will float or sink is dependent on its density, and on the density of the liquid it is placed in. In the case of water, an object with a density less than 1 g/cm3 will float. The closer its.

lighter than water. If an item is heavier than water it will sink. If it is lighter than water it will float. 2. Show the students the items which will be tested. Ask the students to predict which items will float and sink. Place each item in the water one at a time and observe if it sinks or floats. 3 However, if we place it on the box then a huge portion of the box will sink under the surface, displacing far more than a cubic millimeter of water. Edit based on the edit in the question: Under the majority of circumstances, water is, for all intents and purposes, incompressible As a result, objects floating in water will sink or change shape as the surface tension changes. In this activity you'll explore how surface tension affects the behavior of objects in water. B) Why does an object float or sink when placed on the surface of water? C) What do you mean by Buoyancy. 23. A) Derive an expression for kinetic energy of a moving body. B) Name the type of energy possessed by i. Flowing water ii. Stretched rubber band D) A car weighing 2000 Kg is accelerated from rest and covers a distance of 40 m in 6 sec. calculate the work done by the car

The cup will sink if and only if the total downward force pushing on all its upward facing surfaces, plus its own weight, is stronger than the total upward force pushing on its downward facing surfaces.. If the cup is full, then the weight of the water inside it pushes down on the upward facing surface of the inside of the bottom of the cup (and possibly one or more internal side surfaces, if. 2. Make a prediction about each object - do you think it will sink or float in the tub of water? (To make a prediction means to say what you think will happen.) Mark your prediction on the worksheet for each item (circle float or sink). 3. Drop the objects into the water one at a time. Watch what happens to each one. Did you predict correctly Why does an object float or sink when placed on the surface of water? Solution: When the object has density less than 1 g cm-3 (density of water), then it floats on the surface of water, because, it always displaces more weight of water than its own weight. As buoyant force is more than its own weight, therefore, it floats

Why does an object float or sink when placed on the surface of the water? Answer: Upward thrust of liquids, (different-in liquid densities) Sink of an object depends upon density. The density of an object is more than water then it sinks. Object density is less than that of water it floats. Question 10 Figure 14.19 (a) Even objects that sink, like this anchor, are partly supported by water when submerged. (b) Submarines have adjustable density (ballast tanks) so that they may float or sink as desired. (c) Helium-filled balloons tug upward on their strings, demonstrating air's buoyant effect If an object is less dense than water it will sink into the water until the mass of water displaced equals the mass of the object. If pushed further under it will float back up. If the object is of equal density it will sink into the water so that no part of the object is above the surface Yes. But it's a bit more than that. The ability to float depends on the density of the object relative to the material in which it is placed. Thus, an block made from iron (density of about 7.8 g/cm^-3) will sink in water (density 1 g/cm^-3). Ditt..

If an object is less dense than the water or air surrounding it, the object floats; if the object is denser, it sinks. Surface tension is a property that makes the surface of a liquid act like a. 22. Why does an object float or sink when placed on the surface of water? Ans: If the density of an object is more than water, it will sink in water. If the density of an object is less than water, it floats. 23. You have a bag of cotton and an iron bar each indicating a mass of 100kg when measured on a weighing machine

18. Why do objects float or sink when placed on the surface of a fluid? 1. A body sinks if its weight is greater than the buoyant force acting on it. Weight > buoyant force Apparent weight = weight - buoyant force. 2. A body floats if buoyant force balance the weight of the body compared to the same amount (volume) of water. This ratio of an object's mass to its volume is known as density. Density is what really determines whether something will sink or float. Therefore, we say that if something's density is lesser than the water's density, then it will float on water's surface, otherwise it will sink If an object floats on the surface displaces 10 cm3 of water, how much does that object weigh? Explain. The object weigh 10 grams, since the density of water is 1, you divide 10 by 1 equals to 10 grams

Buoyancy is the ability of an object to float in a fluid (liquid or gas) An objects floats when in water if the buoyancy force of the water pushing the object up is greater than the force of gravity pulling the object down.. Weight measures the force of gravity acting on an object. Buoyancy is a force equal to the weight of water displaced by an object when it is placed in water An object placed in a fluid such as water can do three things: It can sink. We call this negative buoyancy. It can float. We call this positive buoyancy. If we push the object below the surface of the water and let go, the positive buoyancy force pushes it back up again above the surface. It can stay submerged below the surface and neither sink. Place one item into the water at a time. Talk about why some objects sank and others didn't. Discuss the weight, size and material the object is made of and how this influences the floating ability. Talk about why there were bubbles when some objects sank. Read books about floating and sinking Observe whether each material float on water or sink to the bottom of the bucket. Observations: Some materials like dry leaf, pencil, wooden piece and table tennis ball float on the surface of water. Materials like eraser, pebble and iron nail sink to the bottom of the bucket. Conclusion: Some materials float on water while others sink

### Why do objects float or sink in water

1. Understand how mass and surface area affect an object's ability to float; Form hypotheses and ask questions about how objects float; Vocabulary. B uoyancy: Describes whether an object will float or sink in a given fluid. An upward force exerted by a fluid on an immersed object. D ensity: The amount of mass per unit volume (mass/volume)
2. How Objects Float in Fluids. by Ron Kurtus. The way that objects float is that at any depth in a fluid there is an upward force due to the effect of gravity on the fluid. This results in a pressure applied over an area. If the density of an object in the fluid is greater than the density of the fluid, the object will sink
3. Why does an object float or sink when placed on the surface of water? Answer: Due to this reason, a block of plastic released under water comes up to the surface of the water. Question 21: The volume of 50 g of a substance is 20 cm 3. If the density of water is 1 g cm −3.
4. an object will float on the surface of water when it has density less than that of water because it always displaces more weight of water than its own weight, and as the buoyant force is more than its own weight, therefore it floats. on the other hand, an object sinks in water when it has density more than that of water because it always displaces less weight of water than its own weight, and.
5. If you put an egg in a cup of tap water, it will sink to the bottom. But, if you add enough salt, the egg will float back up to the surface! Why is this? Because the density of the egg is higher than the density of tap water, the egg sinks. Density is the mass of a material per unit volume
6. In what direction does the buoyant force on an object immersed in a liquid act? Why a block of plastic does release underwater come up to the surface of the water? The volume of 50 g of a substance is 20 cm3. If the density of water is 1 g cm-3, will the substance float or sink? The volume of a 500 g sealed packet is 350 cm3

Many objects can be made of materials denser than water and still float. For example, ships made out of very dense steel can stay afloat just fine. The reason has to do with the shape of the object, and with how it's displacing water. This is true for materials of any density. Think about this - say you have a type of rubber which is denser. POTATO FLOAT Unit: Salinity Patterns & the Water Cycle l Grade Level: Middle l Time Required: 30 min. (in class) after solutions are prepared by the teacher l Content Standard: NSES Physical Science, properties and changes of properties in matter | Ocean Literacy Principle 1e: Most of Earth's water (97%) is in the ocean. Seawater has unique properties: it is saline, its freezing point is. SALT WATER DENSITY SET UP: STEP 1: Start by filling one glass about 2/3 of the way full with water. Ask the kids what will happen if you carefully drop an egg into the glass of water. Now go ahead and do it! STEP 2: In the other glass, fill to the same height with water. Now stir in 3 tablespoons of salt. Mix well to dissolve the salt A lot of the confusion over bad eggs that do not float seems to be caused by eggs left outdoors in an uncontrolled environment. Its the density in the water and the extra air pockets in the boiled egg that causes it to float. If the inside of an egg rotted and the gas couldn't escape, the mass of the egg would be unchanged. Once the bowl is full of water, simply place an egg into the water.

### Why Do Objects Float And Sink - thestanforfamily

1. Once that's set, follow these steps to put in colored contacts effectively. Stand on a flat surface where you have low chances of losing your lens. If you are standing over the sink, it's best to plug the drain to prevent the lens from being lost. Now, place one lens on your index finger. The outside 9 colored side) must be pointing down at.
2. An object can float or sink on the surface of water for two reasons; 1) If the density of the object is less than water then it will normally float on the surface of the water. 2) If the object is heavier than the water then we have to increase the surface area of that object with the less amount of mass possible
3. If the density of an object is more than the density of the liquid, then it sinks in the liquid. This is because the buoyant force acting on the object is less than the force of gravity. On the other hand, if the density of the object is less than the density of the liquid, then it floats on the surface of the liquid
4. When an object is immersed in water, the water exerts an upward force on the object. This upward force equal to the weight of water displaced by object is called the buoyant force. If on completely immersing the object, the buoyant force is more than the weight of object will float on water
5. Why objects float or sink when placed on surface of water? Because of the comparative density. If the objects density is greater than water it will sink, if less then it will float
6. Objects float better in salt water (density of salt water is greater than that of pure water). • Water surfaces have a cohesive force (surface tension) that makes them act like a 'skin'. • Small, dense objects (e.g. a pin; a water spider) can 'float' on the surface of water without breaking it, due to surface tension effects
7. um foil. First, lay the foil out flat on top of the water - it will float

You probably know objects can sink or float when placed into water. In both cases the water moves out of the way, or is displaced, to make space for the object Introduce the concept of buoyancy. Explain that when an object is denser than water, it will sink, and when it is less dense than water, it will float. Activity 1: Sink or Float Experiment. Divide into small groups, and give each group a container of water and the objects to be tested. Give each student a Sink or Float worksheet Sink or float experiment with nature. There seems a natural curiosity for kids to add things to water. A sink and float experiment with nature is always lots of fun and a great way to teach them about predicting and testing ideas. It's also a delight watching their face react to the surprise of the expected and unexpected Show them a tub filled with water and the objects that will be tested. Define sink as the action of an object when it becomes submerged in a liquid. Define float as the action of an object when it sits on the surface of a liquid. Explicit Instruction/Teacher modeling. (10 minutes) Have students guess which objects will sink and which will float

### Discover why an object will float or sin

Note: Certain objects like the rubber band and the crayon may seem to float when first placed on the surface of the water. These objects may actually be supported by the water's surface tension and not truly floating as a result of being less dense than water. If students touch the rubber band and crayon and push them a little below the surface how do you decide whether something is going to float or sink in water or any liquid for that matter now I should think well that's very simple if something is very light it's going to float and if something is very heavy it will sink but that is wrong because we know for example ships which are very heavy made of metal can float on water yet something like a spanner or a nail which could be. Children have many preconceived ideas about objects that float or sink. After considering objects that are mostly above the water, several 7-14 year old children described that object as floating. When the object seemed to be directly on top of the water, some children said it was not considered floating because the skin of the water was. Since density is a characteristic property of a substance, each liquid has its own characteristic density. The density of a liquid determines whether it will float on or sink in another liquid. A liquid will float if it is less dense than the liquid it is placed in. A liquid will sink if it is more dense than the liquid it is placed in

### Why does an object float or sink when placed - UrbanPr

example in chemistry the density of water is usually stated as 1 g/cm. 3. In physics, however, the density of water is stated as 1000 kg/m. 3. You will be using this value frequently during today's lab. Float or Sink . When you place an object in a fluid it will do one of two things. It will either float or it will sink Why does an object float or sink when placed on the surface of water? Due to this reason, a block of plastic released under water comes up to the surface of the water. Video Solution for gravitation (Page: 145 , Q.No.: 20) NCERT Solution for Class 9 science - gravitation 145 , Question 20

How Objects Float in Fluids. by Ron Kurtus (revised 13 March 2003) When a solid object is placed in a fluid such as a liquid or gas, there is a buoyant force pushing the object upward. When that force is greater than the downward force of gravity, the object will float to the top of the fluid. Otherwise it will sink or remain in place in the fluid If an object is more dense than water it will sink when placed in water, and if it is less dense than water it will float. If the object is of equal density it will sink into the water so that no part of the object is above the surface. It may or may not float just but entirely below the surface. As eigenperson said, if pushed down it. Some things make it more complicated though. Freshwater has a density which is 2-3% lower than that of seawater. A body will sink faster. Very salty water, like the Dead Sea, has a density of 1. enough to make the object float up to the top. ConcepTest 16.12d Archimedes IV 1) move up slightly 2) stay at the same place 3) move down slightly 4) sink to the bottom 5) float to the top An object floats in waterwith 3/4 of its volume submerged. When oil is poured on top of the water, the object will: A helium balloon in an air-filled glass. Think about a bottle, a cup, or a bowl (or any other similar dish). If you fill up your sink and place an empty container on the surface, it will float. However, as you add water to it, the heavier the object becomes, creating more displacement. Ultimately, there will be too much weight in the cup, and it will sink below the surface

### Why do things float or sink in water? - Quor

Objects either float or sink in water because of something called buoyancy. When an object placed in water weighs less than the amount of water it displaces, it floats. If it weighs more, it sinks. If that cargo ship had been transporting bowling balls, you can bet they wouldn't be cruising the high seas 2. Ask: Will the cork sink or float? Why? 3. Place the cork in the water and let the student see that it floats. 4. Ask: How can we make the cork sink without touching it? 5. Place inverted cup over cork and press, so that the air pressure trapped in the glass displaces the water and seems to make the cork sink. 6. Ask: What. an object will float or sink in a fluid. Why does ice float on water? Why doesn't it sink? Imagine that you use a straw to push an ice cube underwater. Then, you remove the straw. A force pushes the ice up to the water's surface. The force, called buoyant force, is the upward force that fluids exert on all matter. Buoyant Force and Fluid.

### Why Objects Float or Sink When Placed on The Surface of Water

1. 4. Give each group a tub of water, one bag of sink or float objects, and a sink or float worksheet. 5. Have each group take the sink or float items out of their bags and place each one on the table neatly in front of them. Have the students write the names of each item in the column on the left of the worksheet
2. When salt is dissolved in water, as it is in ocean water, that dissolved salt adds to the mass of the water and makes the water denser than it would be without salt. Because objects float better on a dense surface, they float better on salt water than fresh water. The denser the salt water, the easier it is for objects to float on top of it
3. The more it floats, the harder that you will have to squeeze to make it sink. You want it to sink easily. This part may take some fiddling around. 4. Fill your bottle up almost all the way to the top with water. 5. Place the pipet in the water. 6. Top off the bottle until the water reaches the edge of the bottle
4. The buoyant force on a body floating in a liquid or gas is also equivalent in magnitude to the weight of the floating object and is opposite in direction; the object neither rises nor sinks. For example, a ship that is launched sinks into the ocean until the weight of the water it displaces is just equal to its own weight
5. An object will float if it is less dense than the liquid it is placed in. An object will sink if it is more dense than the liquid it is placed in. Summary. Students will investigate a wax candle and a piece of clay to understand why the candle floats and the clay sinks even though the candle is heavier than the piece of clay

to teach people about why objects sink and float. A Cartesian diver and a submarine work in similar ways. In this investigation, you will make a Cartesian diver and examine how the diver in the bottle works like a submarine that dives below the water and then rises back up to the surface. You will observe how changin Why do ships float? If you dropped a small stone into the water, it would sink immediately. But if a block of steel weighing thousands of tonnes were made into a ship, it would float. Any object placed in water experiences two forces: gravity, which pulls it down because of its mass, and the buoyancy force, or upthrust, which pushes it up The buoyant force is present whether the object floats or sinks. Let's consider a floating object, but the analysis is basically the same for a submerged object. We'll also consider a rectangular block, although a similar (more complicated) analysis leads to the same result for funny-shaped objects. The object experiences forces on each of its.

A tin sheet sinks in water because the density of tin is higher than water. But the tin box or boat floats on water because of the trapping of large amount of air, whereby the average density of tin box or boat becomes lower than water When an object is immersed in a fluid it experiences an upward force called buoyant force. This property is called buoyancy or upthrust. 10. Why objects float or sink when placed on the surface of water? • Take some water in a beaker. Take a piece of cork and an iron nail of the same mass. Place them on the water. The cork floats and the nail.

### Why Do Things Float in Water? Mental Flos

1. If the force of buoyancy is greater than the force of gravity, the object will float. On the other hand, if the force of gravity is greater, it will sink. If they are equal, the object is said to be neutrally buoyant. A neutrally buoyant object will not float up to the surface or sink down to the bottom when it is in water
2. When placed in a fluid, some objects float due to a buoyant force. (Figure \(\PageIndex{2}\)). If the buoyant force is greater than the object's weight, the object rises to the surface and floats. If the buoyant force is less than the object's weight, the object sinks. If you drop a lump of clay in water, it will sink. But if you.
3. Salt water being denser than freshwater, oil floats on the surface of salt water too. You can check this behavior with corn oil, cooking oil, crude oil, etc. If we immerse ice in oil in a container, it will float. This is because it is less dense than oil. But as it slowly melts into water, it will sink to the bottom
4. That doubt will cause us to falter (just like the dish detergent causes the floating paper clips to sink). The Science behind the Object Lesson. This object lesson on faith, or making bits of metal float on water, is all about surface tension of the water. The water molecules at the surface of water create really strong bonds with one another.
5. um foil boat is on top of the water, it is pushing the water aside, or displacing it. All of this displaced water weighs more than the foil, so it allows the foil boat to float
6. If the object has a higher density than the liquid, it will sink but if it has a lower density, it will float. But I am sure that all of us have seen a counter-example, how it is possible to carefully place a needle on the surface of water and have it float
7. es whether it will float or sink in another substance. An object will float if it is less dense than the liquid it is placed in. An object will sink if it is more dense than the liquid it is placed in

### What Causes Objects to Float or Sink? - Reference

Now if we try to put this object on the surface of water; it will float just like a ship or a leaf on the water surface. But why and How? Here the buyout force is 20/30 metric ton based on design, while the weight is still the 15 metric ton. This surplus buyout force of 5 to 15 metric ton make the cube to float. similarly an increased surface. Archimedes' Principle: Any object, wholly or partly immersed in a fluid, is buoyed up by a force equal to the weight of the fluid displaced by the object. From this principle, we can see that whether an object floats or sinks in water is not based on its own weight, but the amount of water it displaces Q22) Explain why an iron needle sinks in water, but a ship made of iron floats on water. The density of iron is more than the density of water, so the weight of iron is more than weight of water displaced by it and nail sinks. While the shape of an iron ship is made in such a way that it displaces more weight of water than its own weight If that one-cubic-foot pumpkin should happen to weigh 70 pounds, however, it would overcome the 60 pounds of buoyancy and sink. Conclusion. If an object's density is less than that of water's.