Hy does the efficiency of simple machine increase when oil or grease is used carpet is beaten with a stick to remove the dust particles. Why?
Thy is the unit of power called derived unit?
Group
Group 'D'
4*4=16
13. A boy of mass 40 kg runs upstairs and reaches the 8 m high first floor
seconds. Calculate.
a. The force of gravity acting on the boy.
b. The work done by him against gravity.
c. The power of the boy.
bability and sketch the solubility carve of sodium chlorid​