Advertisements
Advertisements
Question
Give reasons for the following:
Telephone wires sag in summer.
Advertisements
Solution
Telephone wires sag in summer because due to heat of the sun, the wire expands and increases in length, thus they sag in summer.
APPEARS IN
RELATED QUESTIONS
Kerosene contracts on heating.
A longer rod expands ........... than a shorter rod on being heated to the same temperature.
State three factors on which depend the linear expansion of a metal rod on heating.
A cubical metal solid block is heated. How will its volume change?
An empty glass bottle is fitted with a narrow tube at its mouth. The open end of the tube is kept in a beaker containing water. When the bottle is heated, bubbles of air are seen escaping into water. Explain the reason.
Water is heated from 0°C to 4°C. Will it expand?
The diagram shows a sketch graph showing a change in volume of a given mass of ice at -5°C to water at 15°C.

(i) Why does the temperature along BC remain constant?
(ii) When is the volume of water minimum?
(iii) At what temperature does water have maximum density? Explain.
Complete the following sentence:
When ice melts its volume ______ and density _______.
Give reason for the following
An ordinary glass bottle cracks when boiling water is poured into it, but a borosilicate glass bottle does not.
