A BOOK OF WEIGHT 20N IS PRESSED BETWEEN TWO HANDS AND EACH HAND EXERTS 40N FORCE. IF BOOK JUST STARTS TO SLIDE DOWN. COEFFICIENT OF FRICTION IS?
A BOOK OF WEIGHT 20N IS PRESSED BETWEEN TWO HANDS AND EACH HAND EXERTS 40N FORCE. IF BOOK JUST STARTS TO SLIDE DOWN. COEFFICIENT OF FRICTION IS?










