Electricity — Science STD 10 — Question

A student traces the path of a ray of light through a rectangular glass slab for four different angles of incidence. He very cautiously measures the angle f, angle r and the angle e. On analysing his measurements, he is likely to draw the following conclusion:

The unit of what is named oersted in honour of Hans Oersted:

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 major cause of environmental pollution is the use of:

1. Hydrogen as fuel.
2. Biomass energy.
3. Ocean energy.
4. Fossil fuels.

Linear magnification produced by a convex lens can be:

1. Less than 1 or more than 1.
2. Less than 1 or equal to 1.
3. More than 1 or equal to 1.
4. Less than 1, equal to 1 or more than 1.

Near and far points of a young person normal eye respectively are:

In which of the following, the image of an object placed at infinity will be highly diminished and point sized?

1. Concave mirror only.
2. Convex mirror only.
3. Convex lens only.
4. Concave mirror, convex mirror, concave lens and convex lens.

After testing the eyes of a child, the optician has prescribed the following lenses for his spectacles:
Left eye: +2.00D
Right eye: +2.25D
The child is suffering from the defect of vision called:

_________________ send signals to the brain:

The eye consists of a screen called ______ on which the light rays are focused: