31.

An uncharged particle is moving with a velocity $\overrightarrow{\mathrm{v}}$ in non-uniform magnetic field as shown.

  

velocity $\overrightarrow{\mathrm{v}}$ would be

• Maximum at A & B 

• Minimum at A &  B

• Maximum at M

• same at all points

Which of the following is true regarding diamagnetic substaces symbols ( symbols have their usual meaning)

• μ > 1, χ_m > 1

• μ > 1, χ_m < 1

• μ_r < 1, χ_m < 1

• μ >1, χ_m < 1

What would be the voltage across C₃?

• $\frac{\left({\mathrm{C}}_1 + {\mathrm{C}}_2\right) \mathrm{V}}{{\mathrm{C}}_1+ {\mathrm{C}}_2 + {\mathrm{C}}_3}$

• $\frac{{\mathrm{C}}_1 \mathrm{V}}{{\mathrm{C}}_1 + {\mathrm{C}}_{2 }+ {\mathrm{C}}_3}$

• $\frac{{\mathrm{C}}_2 \mathrm{V}}{{\mathrm{C}}_2 + {\mathrm{C}}_2 + {\mathrm{C}}_3}$

• $\frac{{\mathrm{C}}_3 \mathrm{V}}{{\mathrm{C}}_1 + {\mathrm{C}}_2 + {\mathrm{C}}_3}$

A galvanometer has a current sensitivity of  1 mA  per division.  A variable shunt is connected across the galvanometer and the combination is put in series with a resistance of 500 Ω  and cell of internal resistance 1 Ω  It gives a deflection of 5 division for shunt of 5 ohm and 20 division for shunt of 25 ohm. The emf of cell is

• 47.1 V

• 57.1 V

• 67.1 V

• 77.1 V

A circular coil with a cross-sectional area of  4 cm²  has 10  turns. It is placed at the center of a long solenoid that has 15 turns/cm and a cross-sectional area of IO cm2, as shown in the figure. The axis of the coil conicides with the axis of the solenoid. What is their mutual inductance?

• 7.54 μH

• 8.54 μH

• 9.54 μH

• 10.54 μH

An electric charge 10^-3 μC is placed at the origin (0,0) of (x-y) co-ordinate system. Two points A and B are situated at  $\left(\sqrt{2}, \sqrt{2}\right)$ and (2,0) respectively. The potential difference between the points A and B will be

• 4.5 volt

• 9 volt

• Zero

• 2 volt

In the circuit shown, current flowing through 25 V cell is

• 7.2 A

• 10 A

• 12 A

• 4.2 A

Alternating current cannot be measured by D.C ammeter because

• A.C cannot pass through D.C parameter

• A.C changes direction

• average value of current for complete cycle is zero 

• D.C ammeter will get changed

The core of any transformer is laminated so as to

• reduce the energy loss due to eddy currents

• make it light weight

• make it robust &  strong

• D.C ammeter will get damaged

Assertion:  An electric field is preferred in comparison to magnetic field for detecting the electron beam in a television picture tube. 

Reason:  Electric field requires low voltage.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false.

• If both assertion and reason are false.