Light – Reflection and Refraction — Science STD 10 — Question

An MCB which cuts off the electricity supply in case of short-circuiting or overloading works in the:

1. Chemical effect of current.
2. Heating effect of current.
3. Magnetic effect of current.
4. Electroplating effect of current.

The angle between the two refracting surface of a prism is called angle of:

An object is placed at a large distance in front of a concave mirror of radius of curvature 40cm. The image will be formed in front of the mirror at a distance:

A student has obtained a point image of a distant object using the given convex lens. To find the focal length of the lens he should measure the distance between the:

The human eye can focus objects at different distances by adjusting the focal length of the eye-lens. This is due to:

1. Presbyopia.
2. Accommodation.
3. Near-sightedness.
4. Far-sightedness.

Refraction of light in the eye occurs at:

The resistance of hot filament of the bulb is about 10 times the cold resistance. What will be the resistance of 100W - 220V lamp, when not in use?

The clear sky appears blue because:

1. Blue light gets absorbed in the atmosphere.
2. Ultraviolet radiations are absorbed in the atmosphere.
3. Violet and blue lights get scattered more than lights of all other colours by the atmosphere.
4. Light of all other colours is scattered more than the violet and blue colour lights by the atmosphere.

One of the following does not contribute to acid rain. That is:

1. Nitrogen monoxide.
2. Sulphur dioxide.
3. Carbon monoxide.
4. Carbon dioxide.

A student traces the path of a ray of light through a triangular glass prism for different values of angle of incidence. On analysing the ray diagrams, which one of the following conclusions is he likely to draw?