Practice Questions set 4 - general science mcq Online Quiz (set-1) For All Competitive Exams

Q-1)   An electric bulb is connected to 220 V generator. The current is 0.5A. The power of the bulb is

(a)

(b)

(c)

(d)


Q-2)   In electric apparatus ‘Earth’ is used

(a)

(b)

(c)

(d)


Q-3)   An alternating current can be converted into direct current by a

(a)

(b)

(c)

(d)


Q-4)   Gases are good conductors of electricity at

(a)

(b)

(c)

(d)


Q-5)   Refractive index of an optical medium changes with
  1. the nature of the medium.
  2. the change in the angle of incidence of the ray.
  3. colour of the incident ray.
Select the correct answer using the code given below:

(a)

(b)

(c)

(d)


Q-6)   In the figure shown below, $L_1$ and $L_2$ are two lenses and are kept along the same axis. A parallel beam of light falling on $L_1$ leaves $L_2$ as a parallel beam: Consider the following statements.
  1. Both L1 and L2 can be convex lenses.
  2. The distance between the two lenses can be equal to sum of their focal lengths.
Which of the statements given above is/are correct ?

electricity magnetism light question answer 39

(a)

(b)

(c)

(d)


Q-7)   The energy band gap is minimum in

(a)

(b)

(c)

(d)

Explanation:

Maximum in insulators and minimum in metals.


Q-8)   The polarity of an unmarked horse shoe magnet can be determined by using

(a)

(b)

(c)

(d)


Q-9)   An oscillator is nothing but an amplifer with

(a)

(b)

(c)

(d)

Explanation:

A positive feedback from output to input in an amplifier provides oscillations of constant amplitude.


Q-10)   The filament of a halogen lamp is an alloy of

(a)

(b)

(c)

(d)