An electric lamp is rated 240V, 40W. What is the cost of running the lamp for 72 hours if the electricity authority charges N2.50 per kWh?

Which of the following statements about a spring balance and/or a chemical balance is not correct?

A wheel and axle of radii 800mm and 200mm respectively is used to raise a body of weight 800N by the application of 250N. Calculate the efficiency of the mac...

Each of the following physical quantities is classified as a vector or a scalar quantity. Which of the classifications is correct?

Which of the following phenomena is the practical evidence for the existence of the continual motion of molecules?

Masses,m1 and m2 at the 20-cm and 65-cm marks respectively of a uniform metre rule freely suspended at its centre of gravity. If the metre rule balances hori...

A body of mass 25kg, moving at 3ms-1 on a rough horizontal floor is at rest after sliding through a distance of 2.50m on the floor. Calculate the co-efficien...

Which of the following simple machines is a second class lever?

The friction which exists between two layers of liquid in relative motion is called