A hot object loses heat to its surroundings in the form of heat radiation. The rate of loss of heat depends on
the
(A) temperature of the object
(B) temperature of the surroundings
(C) temperature difference between the object and its surroundings
(D) average temperature of the object and its surroundings
Yellow colour light is used as fog because yellow colour
(A) light is most scattered by fog
(B) has the longest wavelength among all colours
(C) has the longest wavelength among all colours except red and orange but the red colour is already used for
brake light and stop light where as organe colour is avoided due to its similarly with red
(D) has the shortest wavelength among all colours not already reserved for other purpose
The process of nuclear fusion in the sun requires
(A) very high temperature and very high pressure
(B) low temperature and high pressure
(C) high temperature and low pressure
(D) very high temperature and no pressure
Which one among the following statements about thermal conductivity is correct ?
(A) Steel > Wood > Water (B) Steel > Water > Wood
(C) Water > Steel > Wood (D) Water > Wood > Steel
A swinging pendulum has its maximum acceleration at
(A) the bottom of the swing (B) the two extremities of the swing
(C) every point on the swing (D) no particular portion of the pendulum
Which one among the following is an electrochemical cell that cannot be charged ?
(A) Electrolytic cell (B) Storage cell
(C) Primary cell (D) Fuel cell