158. The kinetic energy of electrons ejected by using light having frequency equal to threshold frequency (v0
) is
1) hv0
2) Almost zero 3) Very large 4) h/v0
159. An oil drop has 6.39 x 10-19 charge. What will be the number of electrons in this drop
1) 2 2) 4 3) 8 4) 16
160. An isotone of 76
33 As is
a) 77
32Ge b) 77
33 As c) 77
34 Se d) 78
34 Se
1) Only a and b 2) Only b and d 3) Only b and c 4) b, c and d
161. The number of neutrons present in the deuterim isotope of hydrogen is
1) 2 2) 3 3) 5 4) 1
162. Identify the incorrectly matched set from the following
List I List II
1) Wavelength Nanometers
2) Frequency Hertz
3) Wavenumber m-1
4) Velocity ergs