A stone is projected horizontally from the top of a tower with a speed of 5ms-1. It lands on the ground level at a horizontal distance of 20m from the foot of the tower. Calculate the height of the tower. (g = 10ms\(^{-2}\))

In an electrolysis experiment, the ammeter records a steady current of 1A. The mass of copper deposited is 0.66g in 30 minutes. Calculate the error in the ammeter reading (Electrochemical equivalent of copper = 0.00033g C\(^{-1}\)).

(a) What is surface tension?

(b) State two methods by which the surface tension of a liquid can be reduced.

(a) Define Young's modulus.

(b) State the physical quantities one has to measure in order to determine the Young's modulus of a wire.

(a) What is the principle upon which the lighting in fluorescent tubes operate?

(b) State two factors on which the colour of light from a fluorescent tube depends.