Physics - Study Mode
[#341] On a clean glass plate a drop of water spreads to form a thin layer whereas a drop of mercury remains almost spherical because:
Correct Answer
(C) cohesion of mercury is greater than its adhesion with glass.
Explanation
Solution: On a clean glass plate a drop of water spreads to form a thin layer whereas a drop of mercury remains almost spherical because cohesion of mercury is greater than its adhesion with glass.
[#342] Suitable impurities are added to a semiconductor depending on its use. This is done in order to
Correct Answer
(C) increase its electrical conductivity
Explanation
Solution: Suitable impurities are added to a semiconductor depending on its use. This is done in order to increase its electrical conductivity.
[#343] Stars twinkle because
Correct Answer
(C) the refractive index of the different layers of the earth's atmosphere changes continuously.
Explanation
Solution: Stars twinkle because the refractive index of the different layers of the earth's atmosphere changes continuously.
[#344] It takes much longer to cook food in the hills than in the plains, because
Correct Answer
(A) in the hills the atmospheric pressure is lower than that in the plains and therefore water boils at a temperature lower than 100 o C causing an increase in cooking time
Explanation
Solution: It takes much longer to cook food in the hills than in the plains, because in the hills the atmospheric pressure is lower than that in the plains and therefore water boils at a temperature lower than 100 o C causing an increase in cooking time.
[#345] Moment of inertia is:
Correct Answer
(D) Tensor
Explanation
Solution: Moment of inertia is tensor.