243. Match the following:
            A. Voltmeter                       1.    Measurement of
                                                     potential difference
            B.   Ammeter                       2.    Measurement of
                                                     electric current
            C.   Galvanometer                  3.    Measurement of
            D.   Potentiometer                 4.    Detection of electric
             A         B          C          D
       (a)   1         2          3          4
       (b)   4         3          1          2
       (c)   1         2          4          3
       (d)   3         4          2          1
Ans : (c)
244. Suppose a piece of ice is dropped in a glass of water so that the level of water is on the brim. After melting of ice:
       (a) the water level of the glass will fall
       (b) the water level will rise and some water will over flow the glass
       (c) the water level will remain the same
       (d) the fall or rise of water level will depend on the size of the ice-piece
Ans : (c)
245. A drop of liquid always try to assume a spherical shape because:
       (a) the surface of a sphere is maximum for a given volume
       (b) the surface of a sphere is minimum for a given volume
       (c) the intramolecular forces are strong in. liquid
       (d) the spherical shape provides the best possible balance of intramolecular force within the given volume of liquid
Ans : (b)
246. Suppose a rocketship is receding from the, ili earth at a speed of 2/10 th the velocity of light. A light in the rocketship appears blue
     to the passenger on the ship. What colour would it appear to an observer on the earth?
       (a) Blue
       (b) Orange
       (c) Yellow
       (d) Yellow-Orange
Ans : (c)
247. It is not sufficient to bring a piece of ice to its melting point to melt it. An additional amount of heat energy is required to turn such
     solid into water at the same temperature and such extra amount of heat required is called:
       (a) heat of fusion
       (b) heat of fission
       (c) latent heat of liquidation
       (d) heat of transformation
Ans : (a)
248. Remote Sensing Satellites are called Polar Satellites because:
       (a) they orbit the earth along the poles or from pole to pole
       (b) they are fixed at a particular point
       (c) the axis of satellite is always pointed, towards the pole
       (d) None of the above
Ans : (a)