A hydrogen balloon floats up because of
A). Air pressure decreases with decrease in height
B). Air pressure decreases with decrease in weight
C). Weight of the balloon is less than the weight of air displaced by it.
D). The pressure inside the balloon is more than the pressure outside it
Weight of the balloon is less than the weight of air displaced by it.
The balloon has to displace some air, so in response, the air pushes up on it. But hydrogen is less dense than air, so the air pushes up on the balloon harder than gravity is pulling it down, and the balloon tries to move up. So just like wood float on water, hydrogen balloons float on air.
2. A periscope works on the principle of
3. The atmospheric layer reflecting radio waves is called
4. An athlete runs before long jump to get advantage on
5. Optical fibers are based on the phenomenon of
6. A spherical ball made of steel when dropped in mercury container will
7. What is the direction of torque?
8. Which among the following types of coal produces most heat per unit?