Advertisements
Advertisements
प्रश्न
If a fresh egg is put into a beaker filled with water, it sinks. On dissolving a lot of salt in the water, the egg begins to rise and then floats. Why ?
उत्तर
When a large amount of salt is dissolved in water, the density of salt solution becomes higher than pure water. It is because of its higher density, the salt solution exerts a greater upward buoyant force on the egg, making it rise and then float.
APPEARS IN
संबंधित प्रश्न
What is the unit of relative density?
Explain the meaning of the statement
‘Relative density of aluminium is 2.7’.
Which of the following will sink or float on water? (Density of water = 1 g Cm-3)
body D having density 0.85 g m-3
Define the term thrust. State its S.I. unit.
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.
What is the centre of buoyancy? State its position for a floating body with respect to the centre of gravity of the body.
A body is held inside water contained in a vessel by tying it with a thread to the base of the vessel. Name the three forces that keep the body in equilibrium, and state the direction in which each force acts.
The blood pressure reading of a patient is recorded 160/100. Express the lower pressure in SI units.
[Take density of mercury as 13.6 × 103 kgm−3 and the value of ‘g’ as 10 ms−2]
Is pressure a vector quantity?
Icebergs and ships stay afloat due to ______.
