Question

Assertion :   A paramagnetic sample display greater magnetisation (for the same magnetising field) when cooled.

Reason     : The magnetisation does not depend on temperature.

(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.

Answer

(c) If assertion is true but reason is false.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

If in a series L - C - R ac circuit, the voltages across L, C and R are V1​, V2​ and V3​ respectively, then the voltage of the source is always.

Unpolarized light falls on two polarizing sheets placed one on top of the other. What must be the angle between the characteristic directions of the sheets if the intensity of the final transmitted light is one-third the maximum intensity of the first transmitted beam

(a) 75°

(b) 55°

(c) 35°

(d) 15°

Light of frequency 4n0 is incident on the metal of the threshold frequency n0. The maximum kinetic energy of the emitted photoelectrons is

(a)   

(b)

(c)   

(d)  

If m is mass of electron, v its velocity, r the radius of stationary circular orbit around a nucleus with charge Ze, then from Bohr's first postulate, the kinetic energy K =  of the electron in C.G.S. system is equal to

(a)   

(b)   

(c)       

(d)   

Two different coils have self-inductance ,. The current in one coil is increased at a constant rate. The current in the second coil is also increased at the same rate. At a certain instant of time, the power given to the two coils is the same. At that time the current, the induced voltage and the energy stored in the first coil are  and  respectively. Corresponding values for the second coil at the same instant are  and   respectively. Then

(a)  

(b)  

(c)

(d) a, b, c 

Beyond which frequency, the ionosphere bands any incident electromagnetic radiation but do not reflect it back towards the earth?
In the propagation of electromagnetic waves the angle between the direction of propagation and the plane of vibration is ________

The minimum intensity of light to be detected by human eye is  . The number of photons of wavelength  5.6   entering the eye, with pupil area  , per second for vision will be nearly

(a) 100

(b) 200

(c) 300

(d) 400

A proton and an electron both moving with the same velocity v enter into a region of magnetic field directed perpendicular to the velocity of the particles. They will now move in circular orbits such that

(a) Their time periods will be same

(b) The time period for proton will be higher

(c) The time period for electron will be higher

(d) Their orbital radii will be same

When a thin transparent plate of thickness t and refractive index m is placed in the path of one of the two interfering waves of light, then the path difference changes by

(a) (m + 1)t

(b) (m – 1)t

(c)   

(d)