Advertisements
Advertisements
प्रश्न
Why are bridges made of steel girders put on rollers?
Advertisements
उत्तर
The beams of the bridges expand maximum during the summer days and contract maximum during the winter nights. If the beams are fixed at both ends on the pillars, they may develop crack due to expansion and contraction. To avoid this, beams are made to rest on rollers on the pillars to provide space for expansion.
APPEARS IN
संबंधित प्रश्न
Fill in the blank
A person is said to have fever if his body temperature is more than _________
What is the Fahrenheit scale of temperature ?
S.I. unit of temperature is :
A small gap is left between two iron rails of the railway track. Why?
State one use of each of the following type of thermometer:
Six's maximum and minimum thermometer.
Assertion (A): 0 °C = 273.16 K. For our convenience we take it as 273 K after rounding off the decimal.
Reason (R): To convert a temperature on the Celsius scale we have to add 273 to the given temperature.
One calorie is the amount of heat energy required to raise the temperature of _______ of water through ______.
