Light – Reflection and Refraction — Science STD 10 — Question

Which scientist suggested that the magnet must also exert an equal and opposite force on the current?

The correct sequencing of angle of incidence, angle of emergence, angle of refraction and lateral displacement shown in the following diagram by digits 1, 2, 3 and 4 is:

A magnet attracts:

1. Plastics.
2. Any metal.
3. Aluminium.
4. Iron and steel.

One of the following does not apply to a concave mirror. This is:

1. Focal length is negative.
2. Image distance can be positive or negative.
3. Image distance is always positive.
4. Height of image can be positive or negative.

Which of the following is not caused by the atmospheric refraction of light?

An object is placed at the following distances from a concave mirror of focal length 15cm, turn by turn:

1. 35cm
2. 30cm
3. 20cm
4. 10cm

Which position of the object will produce:

1. A magnified real image?
2. A magnified virtual image?
3. A diminished real image?
4. An image of same size as the object?

Assertion : A compass needle is placed near a current carrying wire. The deflection of the compass needle decreases when the magnitude of the current in the wire is increased.
Reason : The strength of a magnetic field at a point near the conductor increases on increasing the current.

The lamps in a house hold circuit are connected in parallel because:

The direction of current in the coil at one end of an electromagnet is clockwise. This end of the electromagnet will be:

1. North pole.
2. East pole.
3. South pole.
4. West pole.

Rays from Sun converge at a point 15cm in front of a concave mirror. Where should an object be placed so that size of its image is equal to the size of the object?