Questions
A rectangular block is $10\ cm \times 10\ cm \times 15\ cm$ in size is floating in water with $10\ cm$ side vertical. If it floats with $15\ cm$ side vertical, then the level of water will
- $Rise$
- $Fall$
- $Remain\ same$
- $Change\ according\ to\ density\ of\ block$
A boat having some iron pieces is floating in a pond. If iron pieces are thrown in the liquid then level of liquid
- Increases
- Decreases
- May increase or decrease
- Neither increases nor decreases
A coil of wire of cross-section$0.50$ $m m ^ { 2 }4$ weighs $75g$ in air and $65g$ in water. The length of the coil in cm is
- $\frac { 10 ^ { 2 } } { 50 }$
- $\frac { 10 ^ { 2 } } { 0.50 }$
- $\frac { 10 ^ { 5 } } { 50 }$
- $\frac { 10 ^ { 5 } } { 0.0050 }$
A hollow metal container floats in water, because it displaces _____ weight of water than/as its own weight.
- more
- less
- same
- can't say
A piece of ice floats in a liquid denser than water.The liquid fills the vessel upto the edge. If ice melts completely then:
- water level remains unchanged
- water level decreases
- water overflows
- data is insufficient
State whether the given statement is True or False :
- True
- False
A body of density 5.34 $ \displaystyle g/cm^{3} $ when immersed in water (density 1.0$ \displaystyle g/cm^{3} $ ) will
- float
- sink
- rise
- none of these
A piece of iron [density 7.6$ \displaystyle gcm^{-3} $] sinks in mercury [density 13.6 $ \displaystyle gcm^{-3} $]. State whether true or false.
- True
- False
A piece of iron sinks in water but can float in mercury. True or false.
- True
- False
When an object is placed in a liquid whose density is lower than the object, the object will float. True or false.
- True
- False
A body having density less than 1 $ \displaystyle gcm^{-3} $ floats in water. True or false
- True
- False
why does an iron rod sink in water?
- The density of rod is more than that of water
- The volume of water is more than the weight of the object
- Both A and B
- None of the above
- True
- False
A body of mass 400 g has a volume of 300 cm$^3$. Will body sink in water or not? [Density of water = 1000 kg/m$^3$]
- Sink
- Float
- Sink partly
- Float partly
A slid floats in a liquid in a partially dipped position.
- The solid exerts a force equal to its weight on the liquid
- The weight of the displaced liquid equals the weight of the solid
- The liquid exerts a force of buoyancy on the solid which is equal to the weight of the solid
- The weight of the dipped part of the solid is equal to the weight of the displaced liquid
A balloon lifting in air follows:
- Law of gravitation
- Archimedes principle
- Laws of motion
- all of the above
When a body is wholly or partly immersed in a liquid it experiences.
- An up-thrust or down-thrust depending on the density of the liquid
- An up-thrust
- A down-thrust
- None of the above
The principle on which Hare's apparatus works on is.
- Bernoulli's principle
- Archimedes principle
- Newton's law
- Kepler's law
The upward thrust exerted on the body by the liquid acts vertically upwards through the center of gravity of the displaced liquid.
- True
- False
A body is floating in a given liquid with half of its volume above the surface of the given liquid. If the body is slightly pushed into the liquid, then the body,
- sinks in the liquid and settles at the bottom.
- come back to its position after some time.
- keeps oscillating in vertical direction.
- it jumps into the air and falls on the liquid.
Apparent loss of weight of a body when immersed in a liquid can be explained on the basis of
- molecular theory.
- electron theory.
- Archimedes' principle.
- Bernoulli's principle.
A ball floats on the surface of water in a container exposed to the atmosphere. Will the ball remain immersed at its former depth or will it sink or rise if the container is covered and the air is removed:
- The ball sinks
- The ball rises
- The ball remains immersed at its former depth
- It oscillates
A piece of ice is floating on water in a container. What will happen to the surface of the water when whole ice piece melts
- Will go up
- Will not change
- Will go down
- Noe of these
A wooden block is taken to the bottom of a lake of water and then released . it rise up with a
- Constant acceleration
- Decreasing acceleration
- Constant velocity
- Decreasing velocity
A cube of wood supporting $200 \mathrm { gm }$ mass just floats in water in fully submerged state. When the mass is removed cube rises by $2 \mathrm { cm }$ above water level. Find the size of cube? (take $\rho _ { \text { water } } = 1000 \mathrm { kg } / \mathrm { m } ^ { 3 } )$
- $10 \mathrm { cm }$
- $15 \mathrm { cm }$
- $20 \mathrm { cm }$
- $30 \mathrm { cm }$
A piece of ice is floating in a beaker containing thick sugar solution of water. As the ice melts, the total level of the liquid:
- increases
- decreases
- remains unchanged
- insufficient data
A boat full of scrap iron is floating on water in a lake. If all the iron is dropped into the water, the level of water will:
- go up
- fall down
- remain the same
- Can not be decided.
If a piece of wood just floats in water. What happens to it in ethanol?
- It floats higher
- It stays as before
- It sinks
- First sinks and then rises
Which of the following instrument is used to measure the volume of a solid by water displacement ?
- Thermometer
- Graduated cylinder
- Buret
- Salt bridge
- Conductivity tester
A boat is floating on the surface of water in a tank carrying steel balls. If the balls are thrown into the tank one by one, how will it affect the level of water?
- It will rise
- It will fall
- It will remain unchanged
- First it will rise and then fall
A dog is sitting in a boat which is floating in a pond. If the dog drinks some water from the pond then:
- the level of water in the pond decreases
- the level of water in the pond increases
- the level of water in the pond first increases, then decreases
- the level of water in the pond remains unchanged
A vessel completely filled with water is weighed. This vessel will weigh ________ after a wooden block is gently moved into the water until it stays in equilibrium while any displaced water is removed.
- More
- Same
- Less
- None of the above
A sphere is floating in water its $\dfrac{1}3rd$ part is outside the water and when the sphere is floating in unknown liquid, it's $\dfrac {3}{4}th$ part is outside the liquid than the density of the liquid is
- $\dfrac{4}9\ gm/cc$
- $\dfrac{9}4\ gm/cc$
- $\dfrac{8}3\ gm/cc$
- $\dfrac{3}8\ gm/cc$
A boat carrying steel balls is floating on the surface of water in a tank.If the balls are thrown into the tank one by one , how will it affect the level of water :
- It will remain unchanged
- It will rise
- It will fall
- First it will raise and then fall
Choose the correct statement from the following:
- A body will sink in a liquid if its weight is equal to or greater than the weight of the liquid displaced by it
- A body will float in a liquid if its weight is equal to or less then the weight of liquid displaced by it
- When a body floats in a liquid, the portion of the body above the surface of the liquid is independent of the density of the body relative to that of the liquid
- In still air, a hydrogen filled balloon rises up to certain height and then stops rising.
Why an iron nail floats on mercury but it sinks in water?
- Density of iron is more than that of mercury, but less than that of water.
- Density of iron is less than that of mercury, but more than that of water.
- Density of iron is less than that of mercury and water
- Density of iron is more than that of mercury, water.