Practice paper · Kolkata region

The potential energy of an electric dipole placed in a uniform electric field is minimum when the dipole is:

1. AAligned with the field
2. BOpposed to the field
3. CMakes an angle of 45° with the field
4. DMakes an angle of 90° with the field

In Nuclear reaction, there is conservation of

1. AMass only
2. Benergy only
3. Cmomentum only
4. Dmass, energy and momentum

A bulb is connected in series with an inductor and an alternating voltage source. The switch is turned on and the bulb glows. If now an iron rod is inserted in the inductor. The brightness of the bulb will

1. AIncrease
2. Bdecrease
3. Cremain same
4. Dcannot say

A charged particle is moving in a magnetic field ,leaves the field without any deflection

1. AThe particle is positively charged
2. Bthe magnetic field is perpendicular to the direction of motion of the particle
3. Cthe magnetic field is parallel to the direction of motion of the particle
4. Dboth (a) and (c)

In Young double slit Experiment with white source of light, if one slit is covered with green filter and the other with red filter, what will be observed on the screen?

1. AAlternate red and green fringes
2. BAlternate bright and dark fringes
3. CNo interference
4. DThere shall be separate interference pattern for green and red

Which of the following is not due to total internal reflection?

1. AWorking of optical fibre
2. BDifference between apparent and real depth of a pond
3. CMirage on hot summer days
4. DBrilliance of diamond

Which of the following is used to investigate the structure of solids?

1. AGamma rays
2. Binfrared rays
3. CX – rays
4. Dcosmic rays