Which of the following has no effect on radiation?
A blacksmith heated a metal whose cubic expansivity is 6.3 x 10-6K-1. The area expansivity is
A block of ice at its melting point is left on a table in the atmosphere and observed to melt gradually. Which of the following statements is true about the melting process?
Steel bars each of length 3m at 28°C are to be used for constructing a rail line. If the linear expansitivity of the steel is 1 x \(10^{-5}K^{-1}\),what is the safety gap that must be left between the successive bars if the highest temperature expected is 40°C?
Which of the following statements are correct? i. land and sea breezes are natural convection currents. ii. convection may occur in liquids or gasses but not in solids. iii. the vacuum in a thermos flask prevents heat loss due to convection only.
