Physics
Give reasons for the following:
A teacher moving around in the class is doing work but a child standing and reading a book is not doing any work.
Answer
As the teacher moves around in the class, he/she is in a state of motion, there is change in his/her position due to application of force. Hence, work is done by the teacher.
On the other hand, a child standing and reading a book is stationary. There is no change in his/her position. Hence, no work is done by the child.
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