The curie (symbol Ci) is a non-SI unit of radioactivity, named ‘in honour of’ Pierre Curie. It was originally defined as “the quantity or mass of radium emanation in equilibrium with one gram of radium (element)”, but is currently defined as: 1 Ci = 3.7 × 1010 decays per second after more accurate measurements of the activity of 226Ra.

Correct Option: A

The curie (symbol Ci) is a non-SI unit of radioactivity, named ‘in honour of’ Pierre Curie. It was originally defined as “the quantity or mass of radium emanation in equilibrium with one gram of radium (element)”, but is currently defined as: 1 Ci = 3.7 × 1010 decays per second after more accurate measurements of the activity of 226Ra.

In electronics, a choke is an inductor used to block higher-frequency alternating current (AC) in an electrical circuit, while passing lower-frequency or direct current (DC). In a tubelight, the high voltage is created by suddenly interrupting the current in choke, which is connected in series with the tubelight.

Correct Option: A

In electronics, a choke is an inductor used to block higher-frequency alternating current (AC) in an electrical circuit, while passing lower-frequency or direct current (DC). In a tubelight, the high voltage is created by suddenly interrupting the current in choke, which is connected in series with the tubelight.

Washing machines work on the principle of centrifugation. They are based on medium sized centrifuges that put an object in rotation around a fixed axis, applying force perpendicular to the axis. It uses the sedimentation principle, where the centripetal acceleration separates substances of greater and lesser density. Besides, it also makes use of the centrifugal force generated in the “spin cycle” of washing machines that throws the water out through the little holes of perforated drum so that the washed clothes end up much drier.

Correct Option: A

Washing machines work on the principle of centrifugation. They are based on medium sized centrifuges that put an object in rotation around a fixed axis, applying force perpendicular to the axis. It uses the sedimentation principle, where the centripetal acceleration separates substances of greater and lesser density. Besides, it also makes use of the centrifugal force generated in the “spin cycle” of washing machines that throws the water out through the little holes of perforated drum so that the washed clothes end up much drier.

Ice needs to absorb heat energy to melt and become water (called latent heat of fusion). Since sawdust is a poor conductor of heat, it takes more time for the ice to absorb the required heat energy. This allows ice to remain in solid state for more time when packed in saw dust.

Correct Option: C

Ice needs to absorb heat energy to melt and become water (called latent heat of fusion). Since sawdust is a poor conductor of heat, it takes more time for the ice to absorb the required heat energy. This allows ice to remain in solid state for more time when packed in saw dust.

A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction. The process is known as rectification.

Correct Option: C

A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction. The process is known as rectification.