n identical mercury droplets charged to the same potential V coalesce to form a single bigger drop. The potential of the new drop =

 1) nn

 2) n^2/3 n

 3) n/n

 4) n^1/3 n

A shot leaves a gun at the rate of 200 m/s. The greatest distance to which it could be projected is:
1. 200 m
2. 1000 m
3. 2000 m
4. 4000 m

A gaseous mixture enclosed in a vessel of volume V consists of one mole of gas A with γ(=CP?/CV?)=5/3 and another gas B with γ=7/5 at a certain temperature T. The relative molar masses of the gas A and B are 4 and 32, respectively. The gases A and B do not react with each other and are assumed to be ideal. The gaseous mixture follows the equation PV19/13= constant, in adiabatic processes.
Compute the speed of sound in the gaseous mixture at T=300K.

1) v = 501m/s.

2) v = 401m/s.

3) v = 701m/s.

4) v = 801m/s.

If the degrees of freedom of a gas are f, the ratio of its two specific heats, C_P/C_V, is given by:

1) 1 - (1/f)
2) 1 – (2/f)
3) 1 + (1/f)
4) 1 + (2/f)

  If r_p = 3 x 10³ ohm and gm = 20 m. mho if triode is used as an amplifier and RL = 6 kohm, then voltage amplification is

(1) 40
(2) 60
(3) 20
(4) 30

An open container has net 10 gm mass of a radioactive material. The net mass in the container after two mean lives is approximately:

1) 1.35 gm
2) 2.5 gm
3) 10 gm
4) 5 gm

A vessel of volume 0.2m³ contains hydrogen gas at temperature 300K and pressure 1bar1bar. Find the heat (in kcal) required to raise the temperature to 400K. The molar heat capacity of hydrogen at constant volume is (5 cal/molK)

1) 4
2) 2
3) 1
4) 8

When a ray of light enters a glass slab from air
1. Its wavelength increase
2. No change in frequency & wavelength
3. Its frequency increases
4. No change in frequency & wavelength

A photon has momentum 9 × 10⁻⁵⁸ kgms⁻¹. What will be the stopping potential if photo cathode has work function 1.3 eV?

1) 0.49 V
2) 1.4 V
3) 0.59 V
4) 0.39 V

In the basic $$\displaystyle CsCl$$ crystal structure, $$\displaystyle { Cs }^{ + }$$ and $$\displaystyle { Cl }^{ - }$$ ions are arranged in a bcc configuration as shown in the figure. The net electrostatic force exerted by the eight $$\displaystyle { Cs }^{ + }$$ ions on the $$\displaystyle { Cl }^{ - }$$ ion is : 

1) $$\displaystyle \frac { 1 }{ 4\pi { \varepsilon }_{ 0 } } \frac { 4{ e }^{ 2 } }{ 3{ a }^{ 2 } } $$

2) $$\displaystyle \frac { 1 }{ 4\pi { \varepsilon }_{ 0 } } \frac { 16{ e }^{ 2 } }{ 3{ a }^{ 2 } } $$

3) $$\displaystyle \frac { 1 }{ 4\pi { \varepsilon }_{ 0 } } \frac { 32{ e }^{ 2 } }{ 3{ a }^{ 2 } } $$

4)$$\displaystyle zero$$