Physics Past Questions and Answers

A generator is on daily use and in the process, ten 60 W and five 40 W tungsten bulbs are on for the same time interval. the energy consumed daily is?

A 0.96 kWh
B 19.2 kWh
C 9.60 kWh
D 19.20 kWh

Question 32:

The d.c generator has essentially the same components as the a.c generator except the presence of?

A Slip-ring
B Carbon brushes
C Split ring
D Armature

Question 33:

A step-down transformer has a power output of 50 W and efficiency of 80%. if the mains supply voltage is 200 v, calculate the primary current of the transformer.

A 0.31 A
B 3.20 A
C 3.40 A
D 5.00 A

Question 34:

caesium has a work function of 3 x 10^-19J. the maximum energy of liberated electrons when it is illuminated by light of frequency 6.7 x 10¹⁴
HZ is?
[h = 6.6 x 1010^-34Js]

A 1.42 x 10^-19J
B 3.00 x 10^-19J
C 4.42 x 1010^-19J
D 7.42 x 10^-19J

Question 35:

zener diode is used for?

A Current amplification
B Power amplification
C Voltage regulation
D Energy conversion