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प्रश्न
Why do sea divers need special protective suit?
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उत्तर
The sea divers need special protective suit to wear because in deep sea, the total pressure exerted on the diver's body is much more than his blood pressure. To withstand it, he/she needs to wear a special protective suit.
संबंधित प्रश्न
Define buoyant force. Name two factors on which buoyant force depends.
A boy get into a floating boat.
What happens to the buoyant force on the boat ?
Why does a piece of ice float on water?
For a given object, the buoyant force in liquids of different ______ is ______.
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?
A dam has broader walls at the bottom than at the top. Explain.
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.
The pressure P1 at the top of a dam and P2 at a depth h form the top inside water (density p) are related as :
(i) The diameter of neck and bottom of a bottle are 2 cm and 10 cm, respectively. The bottle is completely filled with oil. If the cork in the neck is pressed in with a force of 1.2 kgf, what force is exerted on the bottom of the bottle?
(ii) Name the law/principle you have used to find the force in part (a).
What do you understand by the term upthrust of a fluid? Describe an experiment to show its existence.
