Planets do not twinkle because

A) they emit light of a constant intensity
B) their distance from the earth does not change with time
C) they are very far away from the earth resulting in decrease in intensity of light
D) they are nearer to earth and hence we receive a greater amount of light and, therefore minor variations in the intensity are not noticeable

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Large transformers, when used for some time, become very hot and are cooled by circulating oil. The heating of the transformer is due to

A) the heating effect of current alone
B) hysteresis loss alone
C) both the heating effect of current and hysteresis loss
D) intense sunlight at noon

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Pa(Pascal) is the unit for

A) thrust
B) pressure
C) frequency
D) conductivity

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Nuclear sizes are expressed in a unit named.

A) Fermi
B) angstrom
C) newton
D) tesla

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Find the maximum velocity for the overturn of a car moving on a circular track of radius 100 m. The co-efficient of friction between the road and tyre is 0.2

A) 0.14 m/s
B) 140 m/s
C) 1.4 km/s
D) 14 m/s

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