Electricity — Science STD 10 — Question

If the potential difference between the ends of a fixed resistor is halved, the electric power will become:

1. Double.
2. Half.
3. Four times.
4. One-fourth.

In order to obtain a real image twice the size of the object with a convex lens of focal length 15 cm, the object distance should be:

A beam of parallel light rays is incident through the holes on one side of a box and emerges out through the holes on its opposite side as shown in the diagram below:

Which of the following could be inside the box?

The person is having a defect of vision called:

Light travelling from a denser medium to a rarer medium along a normal to the boundary:

The colour of scattered light depends on.

The other name of potential difference is:

1. Ampereage.
2. Wattage.
3. Voltage.
4. Potential energy.

In these diagrams, the angle of refraction r has been correctly marked in which diagram?

The SI unit of energy is:

1. Joule.
2. Coulomb.
3. Watt.
4. Ohm-metre.