46. A Note is a sound
(a) of mixture of several frequencies
(b) of mixture of two frequencies
(c) of a single frequency
(d) always unpleasant to listen
Answer:
Explanation:
47. How many 176 Ω resistors must be connected in parallel so that the circuit draws 5 A current from a 220 V line?
(a) 2
(b) 3
(c) 4
(d) 5
Answer:
Explanation:
48. If the current, I through a resistor is increased by 100%. (Assume that temperature remains unchanged), the increase in power dissipated will be
(a) 100%
(b) 200%
(c) 300%
(d) 400%
Answer:
Explanation:
49. A constant current flows in a horizontal wire in the plane of the paper from east to west. The direction of magnetic field at a point will be from North to South at
(a) directly above the wire
(b) directly below the wire
(c) at a point located in the plane of the paper, on the north side of the wire
(d) at a point located in the plane of the paper, on the south side of the wire
Answer:
Explanation:
50. A rectangular coil of copper wire is rotated in a magnetic field. The direction of induced current changes once in each:
(a) two revolutions
(b) one revolution
(c) half revolution
(d) one-fourth revolution
Answer:
Explanation: