Question

VII. Define the following: -
1) Non-Luminous bodies.
2) Permanent magnet.
3) Parallel beam of light.
4) Magnetic Substance.
5) Umbra​

Answer 1

Answer:

1. Non luminous bodies are those bodies which do not emit light of their own, but are visible when light falls on those. Planets do not have their own light. They reflect light from the Sun and are thus visible. Stars and the Sun are luminous objects and they emit light

2. a magnet that retains its magnetic properties in the absence of an inducing field or current is called permanent magnet.

3. Parallel beam of light: A parallel beam of light is light that is parallel to each other when coming from the source of light.

4. Magnetic substances are substances that get attracted to magnets. Few of the magnetic substances are - iron, steel, cobalt and nickel. Non-magnetic substances are substances that do not get attracted by a magnet

5. the central part of a shadow where it is completely dark is called umbra.

Answer 2

Explanation:

1. bodies which dont have its own light

2. magnet which always show magnetic field (atract(magnet or metal) or repel other magnet)

3. beam of light which never inrsect eith each other in other word beam of light which never meets.

4. magnetic sustance which has atractive or repulsive nature

5. sorry bro i dont know