Advertisements
Advertisements
प्रश्न
Will a body weigh more in air or vacuum when weighed with a spring balance? Give a reason for your answer.
Advertisements
उत्तर
A body shall weigh more in vacuum because in vacuum, i.e. in absence of air, no upthrust will act on the body.
APPEARS IN
संबंधित प्रश्न
The buoyant force experienced by a body when floating in saltwater is ....... to or same that of when floating in pure water.
Describe an experiment to determine the density of the material of a coin.
A plastic cube is released into the water. Will it sink or come to the surface of the water?
What is meant by pressure? State its S.I. unit.
Pressure at the free surface of a water lake is P1, while at a point at depth h below its free surface is P2. (a) How are P1 and P2 related? (b)Which is more P1 or P2?
The diagram below in Fig. 4.12 shows a device which makes the use of the principle of transmission of pressure.

- Name the parts labelled by the letters X and Y.
- Describe what happens to valves A and B and to the quantity of water in the two cylinders when the lever arm is moved down.
- Give reasons for what happens to valves A and B in part (ii).
- What happens when the release valve is opened?
- What happens to valve B in cylinder P when the lever arm is moved up?
- Give a reason for your answer in part (v).
- State one use of the above device.
In what direction and at what point does the buoyant force on a body due to a liquid act?
A body experiences an upthrust F1 in river water and F2 in sea water when dipped up to the same level. Which is more, F1 or F2? Give reason.
Is pressure a vector quantity?
If the buoyant force is less, the object will float.
