Upthrust

Q. A wooden block is floating in water contained in a beaker . If the beaker is placed in free falling elevator during the free fall the upthrust on the block will be?

Q. An unloaded ship is filled with sand at its bottom so as to:

1. Shift its center of gravity upwards, hence making its equilibrium stable.
2. None of these.
3. Lower its center of gravity, hence making its equilibrium stable.
4. Increase its weight, hence making its equilibrium stable.

Q.

Three objects A, B, and C having density 1.12 g cm-3, 0.92 g cm-3 and 2.02 g cm-3 respectively, are placed in a water tank. Which object will sink in water tank?

1. Only B

2. A and B

3. A and C

4. Only A

Q. A wooden block is floating in water in a beaker. During the free fall of the beaker, the upthrust on the block will be ___.

1. equal to the weight of the block
2. less than the weight of the block
3. zero
4. more than the weight of the block

Q. Why it is easier to swim in sea water than in fresh water?

1. Sea water is more dense than fresh water.
2. Sea water has waves.
3. Fresh water is more dense than sea water.
4. Sea water exerts less upthrust.

Q. A wooden block is floating in water in a beaker. During the free fall of the beaker, the upthrust on the block will be ___.

1. zero
2. more than the weight of the block
3. less than the weight of the block
4. equal to the weight of the block

Q. When a ball is thrown upwards, then its speed until it reaches the maximum height.

1. increases
2. remains the same
3. decreases

Q. Two pieces of metal when immersed in a liquid have equal upthrust on them. Select the correct statement regarding the physical property of the metals given that both of them completely sink in the liquid.

1. Both pieces must have equal weights
2. Both pieces must have equal densitites
3. Both pieces must have equal volumes
4. Both are floating to the same depth