List of top Physics Questions on thermal properties of matter asked in Assam CEE

Two spheres of the same material have radii \(1\,m\) and \(2\,m\), and temperatures \(2000\,K\) and \(1000\,K\) respectively. What is the ratio of energy radiated per second by the first sphere to that by the second?

In a steel plate of length \(100\) cm and breadth \(50\) cm, there is a hole in the shape of an equilateral triangle of side \(10\) cm. The coefficient of linear expansion of steel is \(1.2\times10^{-5}\,{}^{\circ}\mathrm{C}^{-1}\). The temperature of the steel plate is increased by \(100^\circ\mathrm{C}\). What will be the percentage change in the area of the triangular hole?