Q 1 :    

Paramagnetic substances

A. align themselves along the directions of external magnetic field.

B. attract strongly towards external magnetic field.

C. has susceptibility little more than zero.

D. move from a region of strong magnetic field to weak magnetic field.

Choose the most appropriate answer from the options given below:                           [2024]

• A, C only

   

• B, D only

   

• A, B, C, D

   

• A, B, C only

   

Q 2 :    

The coercivity of a magnet is $5\times {10}^3$ A/m. The amount of current required to be passed in a solenoid of length 30 cm and the number of turns 150, so that the magnet gets demagnetised when inside the solenoid is _____ A.                              [2024]

Q 3 :    

Match List-I with List-II                              [2024]

Choose the correct answer from the options given below:

• (A)-(III), (B)-(I), (C)-(IV), (D)-(II)

   

• (A)-(III), (B)-(IV), (C)-(I), (D)-(II)

   

• (A)-(I), (B)-(III), (C)-(II), (D)-(IV)

   

• (A)-(IV), (B)-(I), (C)-(III), (D)-(II)

   

Q 4 :    

The relationship between the magnetic susceptibility ($\chi$) and the magnetic permeability ($\mu$) is given by:

(${\mu }_0$ is the permeability of free space and ${\mu }_r$ is relative permeability)         [2025]

• $\chi =\frac{\mu }{{\mu }_0}–1$

   

• $\chi =\frac{{\mu }_r}{{\mu }_0}+1$

   

• $\chi ={\mu }_T+1$

   

• $\chi =1–\frac{\mu }{{\mu }_0}$

   

Q 5 :    

The percentage increase in magnetic field (B) when space within a current carrying solenoid is filled with magnesium (magnetic susceptibility ${\chi }_{\mathrm{mg}}=1.2\times {10}^{–5}$) is          [2025]

• $\frac{6}{5}\times {10}^{–3}\%$

   

• $\frac{5}{6}\times {10}^{–5}\%$

   

• $\frac{5}{6}\times {10}^{–4}\%$

   

• $\frac{5}{3}\times {10}^{–5}\%$