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State for the following whether it is due to evaporation or condensation:
Steam rising from wet clothes while they are ironed.
Concept: undefined >> undefined
State for the following whether it is due to evaporation or condensation:
Fog appearing on a cold winter morning.
Concept: undefined >> undefined
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State for the following whether it is due to evaporation or condensation:
Blackboard dries up after wiping it.
Concept: undefined >> undefined
State for the following whether it is due to evaporation or condensation:
Steam rising from a hot girdle when water is sprinkled on it.
Concept: undefined >> undefined
Water vapour is present in air only during the monsoon.
Concept: undefined >> undefined
Water evaporates into air from oceans, rivers, and lakes but not from the soil.
Concept: undefined >> undefined
The process of water changing into its vapour, is called evaporation.
Concept: undefined >> undefined
Water vapour condenses to form tiny droplets of water in the upper layers of air where it is cooler.
Concept: undefined >> undefined
Suppose you want to dry your school uniform quickly. Would spreading it near an anghiti or heater help? If yes, how?
Concept: undefined >> undefined
Take out a cooled bottle of water from refrigerator and keep it on a table. After some time you notice a droplets of water around it. Why?
Concept: undefined >> undefined
To clean their spectacles, people often breathe out on glasses to make them wet. Explain why the glasses become wet.
Concept: undefined >> undefined
Which of the following can never form a circular shadow?
Concept: undefined >> undefined
Three torches A, B and C shown in the following figure are switched on one by one. The light from which of the torches will not form a shadow of the ball on the screen.

Concept: undefined >> undefined
Correct the following statements.
- The colour of the shadow of an object depends on its colour of the object.
- Transparent objects allow light to pass through them partially.
Concept: undefined >> undefined
On a sunny day, does a bird or an aeroplane flying high in the sky cast its shadow on the ground? Under what circumstances can we see their shadow on the ground?
Concept: undefined >> undefined
A torch is placed at two different positions A and B, one by one, as shown in the following figure.

The shape of the shadow obtained in two positions is shown in the following figure.

Match the position of the torch and shape of the shadow of the ball.
Concept: undefined >> undefined
Three identical towels of red, blue and green colour are hanging on a clothes line in the sun. What would be the colour of shadows of these towels?
Concept: undefined >> undefined
A football match is being played at night in a stadium with flood lights ON. You can see the shadow of a football kept at the ground but cannot see its shadow when it is kicked high in the air. Explain.
Concept: undefined >> undefined
A student had a ball, a screen and a torch in working condition. He tried to form a shadow of the ball on the screen by placing them at different positions. Sometimes the shadow was not obtained. Explain.
Concept: undefined >> undefined
In the circuit shown in the following figure, when the switch is moved to ‘ON’ position,

Concept: undefined >> undefined
