Physics Quiz 3

Electrostatic precipitators are used for air pollution control, particularly for removing harmful particulate matter from waste gases at industrial facilities and power-generating stations.

Humidity is a measure of the amount of water vapour in the air. Relative humidity measures the amount of water in the air in relation to the maximum amount of water vapour (moisture). The higher the temperature, the more water vapour the air can hold.

Water and petrol are immiscible with each other and petrol which forms the upper layer continues to burn. Water is heavier than petrol, petrol will come above the water and continue the contact with the atmosphere (oxygen).

Temperature does not affect speed of light. Light is an electromagnetic wave and does not need any material medium to propagate.

Solar energy is converted into chemical energy during Photosynthesis. Photosynthesis is the conversion of solar energy (light energy from the Sun) into stored chemical energy (a form of glucose or other organic molecules).

The function of ball bearings in a wheel is to convert kinetic friction (sliding friction) into rolling friction.

The function of the choke is to provide high voltage initially between the filaments (across the two ends of the tube light) for ionization. Again once the gas in the tube is ionized the choke limits the current flow across the tube.

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.

Due to low air pressure, it is difficult to breathe at higher altitudes. The air at higher altitudes is colder, less dense, and contains fewer oxygen molecules.

Bats, whales, and dolphins, which hunt in darkness or murky water, find their way by using sound. This is called echolocation.