Electrostatics — Physics STD 12 Science — Question

Assertion  :   The specific charge of positive rays is not constant.
Reason      : The mass of ions varies with speed.(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.(c) If assertion is true but reason is false.(d) If the assertion and reason both are false.

The concept of solid angle is a natural extension of a angle to dimensions.

Lenz's law is a direct consequence of:

Which of the following is electromagnetic wave(a) X-rays and light waves(b) Cosmic rays and sound waves(c) Beta rays and sound waves(d) Alpha rays and sound waves

An electromagnetic wave can be produced when the charge is

The dimensions of electric flux are:

A strong argument for the particle nature of cathode rays is that they:

A 25 W, 220 V bulb and a 100 W, 220 V bulb are connected in parallel across a 440 V line(a) Only 100 watt bulb will fuse(b) Only 25 watt bulb will fuse(c) Both bulbs will fuse(d) None of the bulbs will fuse

Assertion  :   The phenomenon of ­X-ray production is basically inverse of photoelectric effect.    
Reason      :  X-rays are electromagnetic waves.(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.(c) If assertion is true but reason is false.(d) If the assertion and reason both are false.

A rod of length 20 cm is rotating with angular speed of 100 rps in a magnetic field of strength 0.5 T about it’s one end. What is the potential difference between two ends of the rod(a) 2.28 V(b) 4.28 V(c) 6.28 V  (d) 2.5 V