(Download) Special Class Railway Apprentices (SCRA) Practice Paper (SET - 1) : Mathematics

A and B are two independent events the probability then both A and B occur is 1/8 and the probability that neither of them occurs is 3/8. The probability of the occurence of the event A is:
(a) 1/3
(b) 1/4
(c) 1/5
(d) 1/8

A wire carrying current i = 100 A is taken. A rod is moved parallel to this wire with a velocity v = 5 m/s as shown in the figure. Find the value of induced emf in the rod.
(a) 2 × 10^–2 volt
(b) 3 × 10^–4 volt
(c) 4 × 10^–3 volt
(d) None of these

A coil has 1,000 turns and 500 cm² as its area. The plane of the coil is placed at right angle to a magnetic induction field of 2 × 10^–5 web/m². The coil is rotated through 180° in 0.2 seconds. The average emf induced in the coil in milli-volts is
(a) 5
(b) 10
(c) 15
(d) 20

When a wheel with metallic spokes 1.2 m long revolves in a magnetic field of 5 × 10^–5 Wbm perpendicular to the plane of wheel, an emf 10^–2V is induced across the rim and the axle of the wheel. Find the rate of rotation of the wheel per second.
(a) 32.2
(b) 44.2
(c) 30.2
(d) None of these

A 10 metre wire is kept in east-west direction. It is falling down with a speed of 5.0 m/s perpendicular to the horizontal component of earth’s magnetic field of 0.30 × 10^–4 Wb/m². What is the momentary potential difference induced between the end of the wires ?
(a) 1.2 mV
(b) 1.6 mV
(c) 2.4 mV
(d) 3.2 mV