Tea or Coffee is sipped from a sáucer when it is hot. Why?

When an iron nail is hammered, it becomes hot. Why?

When wire is bent back and forth, it becomes hot. Why?

When cooking oil is heated in a frying pan, the oil moves around the pan more easily when it is hot. The main reason for this is that with rise in temperature, there is a decrease in

In a survey of 600 students in a school,150 students were found to be taking tea and 225 students were taking coffee.100 were taking both tea and coffee. Find how many students were taking neither tea nor coffee.

The stone tied to a thread is suspending from a spring balance. The spring stretched down when the stone was suspended from it. Why?