Metal rods of length 20cm each are laid end to end to form a bridge at 25°C.What gap will be provided between consecutive rails for the bridge to withstand 75°C? [Linear expansivity of the material = 2.0 x 10-5K-1]
A 50W electric heater is used to heat a metal block of mass 5kg. If in 10minutes, a temperature rise of 12°C is achieved, the specific heat capacity of the metal is
A. 500 J kg-1 K-1 B. 130 J kg-1 K-1
C. 390 J kg-1 K-1 D. 400 J kg-1 K-1