At `20^@C`, the gap between the rails each 50 m in length is observed to be 1.65 cm. If the lines are made of steel `(alpha = 11 xx 10^-6 //^@C)`, at what temperature will the lines just touch?

A copper wire and steel wire both have the same length and radius are joined end to end, when the composite wire is hung from a rigid support, and the load attached at the free end, the increase in the length is found to be 1cm. Find the increase in length of copper steel wire. (Y for copper = 1.2 xx 10^11 N//m^2 , Y for steel = 2.1 xx 10^11 N//m^2)

Railway lines are laid with the gaps to allow for expansion. The gap between two lines is 0.5 cm at 10 °C. If the length of a line is 12 m then temperature at which the lines just touch each other is [alpha = 11 x 1O'6/ °C]

A metal rod of diameter 1 cm measures 50 cm in length at 65 °C. If the coefficient of linear expansion of the rod is 16 x 10-6/ °C, the length of the rod at 0 °C will be

A disc has an area of 0.32 m^2 at 20^@C , what will be its area at 100^@C ? [alpha = 2 xx 10^-6/ @C]

Iron sheet 50 cm X 20 cm is heated through 100^@C . If prop = 12 xx 10^-6//^@C then chnage in area is

Railway tracks are laid with gaps for expansion. The gap between the steel rails 20 m long is 1.2 cm at 10^@C . The temperature at which the steel rails just touch each other is ( prop steel = 12 xx 10^-6//^@C)

A barometer tube of length 90 cm contains some air above mercury. The reading of the mercury level is 74.8 cm when the atmospheric pressure is 76 cm and temperature is 30^@C . If the reading is observed to be 75.4 cm on some another day when temperature is 10^@C , then what will be true pressure?

What is the resistance of one of the rails of a railway track 20 km long at 20^@ C? The cross section area of rail is 25 cm^2 and the rail is made of steel having resistivity at 20^@ C as made of steel having resistivity at 20^@ C as 6 xx 10^-8 Omega m.