Physics Past Questions and Answers

1,000 identical drops of oil of density 500kgm^-3 have a total mass of 5 x 10^-4kg. One of the drops forms a thin film of area 0.5m² on water. The thickness of the film is

The total length of a spring when a mass of 20g is hung from its end is 14cm, while its total length is 16cm when a mass of 30g is hung from the same end. Calculate the unstretched length of the spring assuming Hooke's law is obeyed.

Which of the following statements is CORRECT? i. the mass number is equal to the total number of protons and electrons in an atom. ii. the atomic number is equal to the number of protons in an atom. iii. the number of electrons in an atom is equal to the total number of protons and neutrons in the nucleus.

A short response to time is obtained in liquid-in-glass thermometer when the

A machine has a velocity ratio of 5. It requires a 50kg weight to overcome a 200kg weight. The efficiency is