Which of the following is not true about Frictional force?
Friction is the force which opposes the relative motion of two surfaces in contact.
The force of friction that acts when a body is moving on a surface is called sliding friction.
Friction in machines wastes energy and also causes wear and tear.
Rolling friction is much more than sliding friction, use of ball bearings considerably reduces friction.
Calculate the simple interest if Rs. 1,800 is invested for 10 years at a rate of 5% per annum.