Advertisements
Advertisements
Question
Why do we feel light on our feet when standing in a swimming pool with water up to our armpits ?
Advertisements
Solution
We feel light on our feet when standing in a swimming pool with water up to our armpits because of the buoyant force. It exerts an upward force on our body and makes us feel our apparent weight which is less than our actual weight.
APPEARS IN
RELATED QUESTIONS
Explain the meaning of the statement
‘Relative density of aluminium is 2.7’.
Explain the following statement:
It is easier to cut with a sharp knife than with a blunt one.
Write an expression for the pressure at a point inside a liquid. Explain the meaning of the symbols used.
A dam has broader walls at the bottom than at the top. Explain.
How does the liquid pressure on a diver change if:
the diver moves to the greater depth
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.
Complete the following sentence :
Pressure at all points at the same depth is ....................
The pressure P1 at a certain depth in river water and P2 at the same depth in sea water are related as :
A body will experience minimum upthrust when it is completely immersed in :
A homogeneous block floats on water (a) partly immersed (b) completely immersed. In each case state the position of centre of buoyancy B with respect to the centre of gravity G of the block.
