31.

In  a  series LCR  circuit, the voltage across the resistance, capacitance and inductance is 10 V each. If the capacitance is  short  circuited  the voltage across the inductance will be

• 140 V

• 10 $\sqrt{2}$ V

• 10/ $\sqrt{2}$ V

• 20 V

If v_y , v_x and  v_m are the speeds of gamma rays, X-rays and microwaves respectively in vacuum,  then

• v_y > v_x >  v_m

• v_y < v_x < v_m

• v_y >  v_x >  v_m

• v_y = v_x = v_m

Assertion:  Electric potential of earth is taken zero. 

Reason:  No electric field exists on earth surface.

• 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

Assertion:  A charge, whether stationary or in motion produces a magnetic field around it. 

Reason:  Moving charges produce only electric field in the surrounding space.

• 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

Assertion: Magnetic susceptibillity is a pure number. 

Reason: The value of magnetic susceptibility for vacuum is one.

• 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.

Assertion:  Transformers  are  used  only  in  alternating current  source  not  in  direct current. 

Reason: Only  a.c.  can  be  stepped  up  or  down
by  means  of  transformers.

• 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

Assertion: The dimensional formula for product of resistance and conductance is same as for dielectric  constant.

Reason: Both have dimension of time costant. 

• 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

A  convex  lens  of  refractive  index $\frac{3}{2}$  has  a power of 2.5 D  in  a  liquid  of  refractive  index 2, then  the  new power  of  the  lens  is

• $-$ 1.25 D

• $-$ 1.5 D

• 1.25 D

• 1.5 D

What is the ratio of Bohr magnetron to the nuclear magnetron?

• m_p/m_e

• ${\mathrm{m}}_{\mathrm{p}}^2 / {\mathrm{m}}_{\mathrm{e}}^2$

• 1

• $\frac{{\mathrm{m}}_{\mathrm{e}}}{{\mathrm{m}}_{\mathrm{p}}}$

When the inputs of a two input logic gate are  0  and  0, the output is 1. When the inputs are 1 and 0, the output is zero. The type of logic gate is

• XOR

• NAND

• NOR

• OR