The increase in the width of the depletion region in a \(\mathrm{p\text{-}n}\) junction diode is due to:
1. reverse bias only
2. both forward bias and reverse bias
3. increase in forwarding current
4. forward bias only
A body weighs \(72~\text{N}\) on the surface of the earth. What is the gravitational force on it at a height equal to half the radius of the earth?
| 1. | \(32~\text{N}\) | 2. | \(30~\text{N}\) |
| 3. | \(24~\text{N}\) | 4. | \(48~\text{N}\) |
| 1. | \(1:1\) | 2. | \(1:c\) |
| 3. | \(1:c^2\) | 4. | \(c:1\) |
The quantities of heat required to raise the temperature of two solid copper spheres of radii \(r_1\) and \(r_2\) \((r_1=1.5~r_2)\) through \(1~\text{K}\) are in the ratio:
| 1. | \(\dfrac{9}{4}\) | 2. | \(\dfrac{3}{2}\) |
| 3. | \(\dfrac{5}{3}\) | 4. | \(\dfrac{27}{8}\) |
For which one of the following Bohr models is not valid?
| 1. | Singly ionised helium atom \(\big(\mathrm{He}^{+}\big).\) |
| 2. | Deuteron atom. |
| 3. | Singly ionised neon atom \(\big(\mathrm{Ne}^{+}\big).\) |
| 4. | Hydrogen atom. |
In a certain region of space with volume \(0.2~\text m^3,\) the electric potential is found to be \(5~\text V\) throughout. The magnitude of the electric field in this region is:
| 1. | \(0.5~\text {N/C}\) | 2. | \(1~\text {N/C}\) |
| 3. | \(5~\text {N/C}\) | 4. | zero |
| 1. | \(2.05~\text A\) | 2. | \(2.5~\text A\) |
| 3. | \(25.1~\text A\) | 4. | \(1.7~\text A\) |
What would be the torque about the origin when a force \(3\hat{j}~\text N\) acts on a particle whose position vector is \(2\hat{k}~\text m?\)
| 1. | \(6\hat{j}~\text{N-m}\) | 2. | \(-6\hat{i}~\text{N-m}\) |
| 3. | \(6\hat{k}~\text{N-m}\) | 4. | \(6\hat{i}~\text{N-m}\) |
(\(k_B\) is Boltzmann constant and \(T\) absolute temperature)
| 1. | \(\dfrac{3}{2}k_BT\) | 2. | \(\dfrac{5}{2}k_BT\) |
| 3. | \(\dfrac{7}{2}k_BT\) | 4. | \(\dfrac{1}{2}k_BT\) |
A ball is thrown vertically downwards with a velocity of \(20\) m/s from the top of a tower. It hits the ground after some time with the velocity of \(80\) m/s . The height of the tower is: (assuming \(g = 10~\text{m/s}^2)\)
| 1. | \(340\) m | 2. | \(320\) m |
| 3. | \(300\) m | 4. | \(360\) m |
© 2026 GoodEd Technologies Pvt. Ltd.