Physics Past Questions and Answers

(a) Sketch the magnetic flux pattern around a long; straight, current-carrying wire
(b) State two methods by which the sensitivity of a moving-coil galvanometer can be increased.
(c) A series RLC circuit comprises a 100-\(\Omega\) resistor, a 3-H inductor and a 4-\(\mu\)f capacitor. The a.c source of tile circuit has an e.m.f of 100V and a frequency of 160 Hz.
(i) Draw the circuit diagram of the arrangement. Calculate the:
(ii) capacitive reactance;
(iii) inductive reactance:
(iv) impedance of the circuit;
(v) current in the circuit;
(vi) average power dissipated in the circuit.

The diagram above illustrates three forces T₁, T₂ and 100N in equilibrium. Determine the magnitude of T₁

The diagram above illustrates three forces T₁, T₂ and 100N in equilibrium. Determine the magnitude of T₁

An iron rod is moved from the earth to the moon. Which of the following properties of the rod would remain unchanged? i. mass ii. weight iii. relative density

A uniform cylindrical hydrometer of mass 20g and cross sectional area 0.54cm² floats upright in a liquid. If 25cm of its length is submerged, calculate the relative density of the liquid. (Density of water = 1 gcm^-3)