Question

The bulb of a thermometer when dipped in petrol and then taken out, the level of the mercury
thread in the thermometer.

(a) starts falling
(b) starts rising
(c) remains at the same level
(d) initially falls and then rises​

Answer 1

Answer:

(a) starts falling

Explanation:

As the bulb of mercury is taken out of petrol, the petrol which is on the surface of bulb evaporates by the heat of surrounding and the thermometer and makes the surface of bulb, cool. So, the level of mercury will start failing or decreasing.