Physics Quiz 3

The instrument used to see the distant objects on the Earth is a terrestrial telescope. Astronomical telescopes are used for viewing distant stars and planets whereas terrestrial telescopes are used for viewing distant objects on earth.

When warm air (over the fire spot) rises, the air pressure at that place gets lowered. But around it, pressure is high so the air rushes from high-pressure zone to low-pressure zone giving an appearance of fanning the fire.

A geostationary satellite is an earth-orbiting satellite, placed at an altitude of approximately 35,800 km directly over the equator, that revolves in the same direction the earth rotates (west to east). At this altitude, one orbit takes 24 hours, the same length of time as the earth requires to rotate once on its axis. So they seem stationary, relative to the Earth's surface.

A cylindrical lens can be used to treat astigmatism. Astigmatism is a condition that results in the abnormal curvature of your cornea or the lens of your eye.

Optical fibre works on the principle of total internal reflection. When light ray strikes at the internal surface of an optical fibre cable called such that incidence angle is greater than critical angle, then incident light ray reflects in the same medium and this phenomenon repeats.

All objects, regardless of mass, will fall at the same rate. Heavier things have a greater gravitational force AND heavier things have a lower acceleration. It turns out that these two effects exactly cancel to make falling objects have the same acceleration regardless of mass.

A battery is a DC voltage source that converts chemical energy to electrical energy. The chemical reactions in a battery involve the flow of electrons from one material (electrode) to another, through an external circuit.

Smog is a kind of air pollution. The smoke usually came from large amounts of coal burning in an area and is caused by a mixture of smoke and sulphur dioxide (SO₂).

Helium-3 is a gas that has the potential to be used as a fuel in future nuclear fusion power plants. There is very little helium-3 available on the Earth. However, there are thought to be significant supplies on the Moon.

Rocket engines and boosters carry both fuel and an oxidizer. For solid fuel, the components are aluminium and ammonium perchlorate. For liquid fuel, the components are liquid hydrogen and liquid oxygen. When combined, the fuels release water, which allows the rocket to leave the ground.