141. The metallic spheres A and B of radii 2m and 4m respectively carry the same charge 4 x 10 8C. If the spheres are connected by a copper wire_______________?
A. charge will flow from A to B
B. charge will flow from B to A
C. no flow of charge will occur
D. both a and b are possible

142. Equipotential planes are_______________?
A. parallel to one another
B. non parallel to one another
C. intersecting
D. circular

143. A 25eV electron has a speed of______________?
A. 2 x 106m/sec
B. 3 x 106m/sec
C. 5 x 106m/sec
D. 4 x 106m/sec

144. capacitor is to have an energy content of 20J it must be placed across a potential difference of________________?
A. 4 volts
B. 9 volts
C. 2 volts
D. 1 vol

145. Two oppositely charged balls A and B attract third conducting ball C when placed near them turn by turn. Then ball C must be______________?
A. positively charged
B. electrically neutral
C. negatively charged
D. positively and negatively charged

146. The only difference between construction of D.C generator and A.C generator is that of_______________?
A. carbon brushes
B. coil
C. commutator
D. magnetic field

147. For electroplating we use_________________?
A. A D.C source
B. an A.C source
C. any source
D. all of the above

148. Energy stored in a magnetic field is given by______________?
A. LI2
B. L2I/2
C. LI2/2
D. IL2

149. Self inductance of a coil depends upon________________?
A. current flowing
B. number of turns per unit length
C. voltage produce
D. all

150. The alternating current has frequency of 106 Hz in such a way that time period for completion of cycle is_______________?
A. 1Hzs
B. 1.5Hzs
C. 106sec
D. 1sec