TNPSC Physics Objective Questions and Answers - 3

Question: 11

The length and diameter of the discharge tube used by J.J. Thomson is ___ respectively.

(A) 25 cm and 4 cm

(B) 50 cm and 4 cm

(C) 75 cm and 8 cm

(D) 60 cm and 6 cm

Question: 12

Gases do not conduct electricity because ____

(A) They have free electrons

(B) They do not have free electron

(C) They are made up of molecules

(D) They are in random motion

Question: 13

In an X-ray tube, the intensity of the emitted X-ray beam is increased by ____

(A) Increasing the filament current

(B) Decreasing the filament current

(C) Increasing the target potential

(D) Decreasing the target potential

Question: 14

Cathode rays ____

(A) Affect the photographic plates

(B) Are deflected by electric and magnetic fields

(C) Are deflected by electric field only

(D) Both (a) and (b)

Question: 15

A micro wave opens uses wave with a

(A) large wavelength in the invisible range

(B) large wavelength in the visible range

(C) small wavelength in the visible range

(D) small wavelength in the invisible range