Physics Past Questions and Answers

An electric heater has a resistance of 50\(\Omega\). When it is immersed in water and connected to mains source, it draws a current of 4.0A. Calculate the heat gained by the water if the heater is switched on for 2 minutes, assuming no heat losses to the surroundings

When salt is dissolved in water, the freezing point of the water

The equation of a certain progressive transverse wave is y = 2 sin 2 \(\pi ( \frac{t}{0.01} - \frac{x}{30})\), where x and y are in cm and t in seconds. Calculate the period of the wave.

At which position should an object be placed in front of a concave mirror in order to obtain an image which is of the same size as the object?

Images formed by a convex mirror are always