IGCSE Physics Paper-1: Specimen Questions with Answers 53 - 54 of 149

In which of the circuits below both lamps are protected by the fuse?

Answer

d.

Explanation

Fuse is a simple electrical part, which consist of wire and terminal at each end. It protects the circuit in the event of a large current. When large current pass fuse make circuit open. Thus fuse should be connected in series. For choice 4 only fuse protect both the lamps because in it fuse connected in series with both the lamps.

Cotton is measured between two points on a scale. This cotton is rolled around a pen 6 times. Find the length of each roll?

Answer

d.

Explanation

From first given figure the length of the cotton is measured as,

Now, length of the cotton is wound closely around a pen, and it goes six rounds. So, distance of one round is given as,