The figure below shows four isotropic solids having positive coefficient of thermal expansion. A student predicts that on heating the solid following things can happen. Mark true (T) or False (F) for comments made by the student.

(i) The angle $\alpha$ in figure (1) will not change

(ii) The length of line in figure (2) will decrease.

(iii) The radius of inner hole will decrease.

(iv) The distance AB will increase.

(i) (TRUE)- For the first solid the angle α will not change as the expansion will be uniform from all sides and distance between two adjacent particles of the solid will increase but not the angle between them.

(ii) (FALSE)- For the second solid expansion will result in increase of all dimensions so length of line will also increase and will not decrease.

(iii) (FALSE)- Expansion means separation of all particles of the solid from their adjacent particles, so particles at the boundary of the inner circle will also separate from each other making the circle bigger in radius.

(iv) (TRUE)- The distance between adjacent particles will increase so distance AB will also increase.