Physics Past Questions and Answers

(a) Explain the term resonance and give two examples
(b)(i) Describe, with the aid of a labelled diagram, an experiment to show how the frequency of the note emitted by a vibrating string depends on the length of the string.
(ii) State two precautions necessary to obtain an accurate result.
(c) A sonometer wire is plucked and it vibrates emitting a fundamental note. State the effect on the frequency of the note if the
(i) tension in the wire were made nine times as large with no change in the length of the wire;
(ii) length of the wire were doubled with no change in the tension.

(a) Sketch the form of the magnetic flux pattern due to a current flowing
(i) in a long solenoid
(ii) through two long straight parallel wires when the directions of the current are opposite. (Neglect the earth's magnetic field).
(b) Draw a labelled diagram of an electric bell and explain how it works
(c) An electric bell takes a current of 0.2A groin a battery of two dry cells connected in series. Each cell has an e.m.f. of 1.5V and an internal resistance of 1.0\(\Omega\).
(i) Calculate the effective resistance of the bell
(ii) What current would the bells take in the cells were arranged in parallel?

which of the following pairs of physical quantities comprises vectors?

which of the following pairs of physical quantities comprises vectors?

A piece of stone attached to one end pf string is whirled round in a horizontal circle. When the string is suddenly cut, the stone will