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

Q-1)   Which one of the following is the correct angle between the incident and reflected rays when a ray of light incident normally on a plane mirror?

(a)

(b)

(c)

(d)


Q-2)   Which of the following is the best insulator of electricity?

(a)

(b)

(c)

(d)

Explanation:

Ebonite is the best insulator.


Q-3)   The potential barrier, in the depletion layer, is due to

(a)

(b)

(c)

(d)


Q-4)   Which of the following metals is used as filament in lighting bulbs?

(a)

(b)

(c)

(d)


Q-5)   The resistance of a thin wire in comparison of a thick wire of the same material

(a)

(b)

(c)

(d)


Q-6)   The primary cell which is used in daily life is

(a)

(b)

(c)

(d)


Q-7)   Electric flux at a point in an electric field is

(a)

(b)

(c)

(d)

Explanation:

As area of a point is zero,

∴ φ = E (ds) cosϴ = E cosϴ × 0 = Zero.


Q-8)   An electric lamp of 100 watt is used for 10 hours per day. The ‘units’ of energy consumed in one day by the lamp is

(a)

(b)

(c)

(d)


Q-9)   When a semiconductor is heated, its resistance

(a)

(b)

(c)

(d)


Q-10)   In an A.C. circuit with voltage V and current I the power dissipated is

(a)

(b)

(c)

(d)

Explanation:

Power dissipated = $E_{rms}. I_{rms} = (E_{rms}) (I_{rms})$cosϴ

Hence, power dissipated depends upon phase difference.