Light — PHYSICS STD 7 — Question

The temperature at which a substance in its vapour state changes into its liquid state is called

Select the correct alternative
If a body covers equal distance in equal interval of time, the motion is said to be

A child riding a bicycle possesses

An aeroplane flying straight at a speed of 200 km/h describes :

When calcium carbonate is heated, it changes to calcium oxide and carbon dioxide. The change brought about by the heat energy is :

When is the work done in the following situation :
1.A girl pushing a wall
2. A boy carrying a suitcase ibn h is hand.
3. A stone falling freely
4. A boy climbing up the stairs

When we rub our hands

Accumulators are

An electromagnet is used in

The crack of a thunder cloud is heard later than the flash of lightning because, the light travels :