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#	Question	Subject and topic	Difficulty
51	One kilowatt-hour is equal to:	Physics Electrical energy and power	Medium
52	Electric power is transmitted over long distances at very high voltage mainly because:	Physics Electrical energy and power	Hard
53	A cell of emf 2 V and internal resistance 0.5 Ω is connected to a 3.5 Ω resistor. The terminal voltage is:	Physics Cells, emf and internal resistance	Easy
54	Three identical cells, each of emf 1.5 V and internal resistance 0.5 Ω, are joined in series across a 3 Ω res…	Physics Cells, emf and internal resistance	Medium
55	Two identical cells, each of emf 2 V and internal resistance 1 Ω, are joined in parallel across a 1.5 Ω resis…	Physics Cells, emf and internal resistance	Medium
56	The terminal voltage of a cell equals its emf when:	Physics Cells, emf and internal resistance	Easy
57	A cell of emf E and internal resistance r is being charged by a current I. Its terminal voltage is:	Physics Cells, emf and internal resistance	Hard
58	Kirchhoff’s junction rule is a consequence of the conservation of:	Physics Kirchhoff’s rules and the Wheatstone bridge	Easy
59	Kirchhoff’s loop rule is based on the conservation of:	Physics Kirchhoff’s rules and the Wheatstone bridge	Easy
60	In a Wheatstone bridge, P = 10 Ω, Q = 20 Ω and R = 15 Ω. For balance, S must be:	Physics Kirchhoff’s rules and the Wheatstone bridge	Medium
61	In a meter bridge, a 6 Ω resistor is in the right gap and the unknown resistance in the left gap. The null po…	Physics Kirchhoff’s rules and the Wheatstone bridge	Medium
62	At balance, the condition of a Wheatstone bridge does NOT depend on:	Physics Kirchhoff’s rules and the Wheatstone bridge	Hard
63	Oersted’s experiment first showed that:	Physics Biot-Savart law	Easy
64	A circular loop of radius 0.1 m carries a current of 5 A. The magnetic field at its centre is about:	Physics Biot-Savart law	Medium
65	According to the Biot-Savart law, the field due to a current element is zero at points:	Physics Biot-Savart law	Medium
66	The SI unit of magnetic field B is:	Physics Biot-Savart law	Easy
67	The radius of a current loop is doubled while the current is kept the same. The magnetic field at its centre:	Physics Biot-Savart law	Hard
68	A long straight wire carries a current of 10 A. The magnetic field 5 cm from it is:	Physics Ampere’s law	Easy
69	A long solenoid has 1000 turns per metre and carries 2 A. The field inside it is about:	Physics Ampere’s law	Medium
70	The magnetic field just outside a long ideal solenoid is:	Physics Ampere’s law	Easy
71	The field lines around a long straight current-carrying wire are:	Physics Ampere’s law	Medium
72	The magnetic field at distance r from a long straight wire is B. At distance 3r the field is:	Physics Ampere’s law	Hard
73	A proton moving at 2 × 10⁶ m/s enters a 0.5 T field at right angles. The magnetic force on it is:	Physics Force on moving charges and conductors	Easy
74	Two long parallel wires 0.1 m apart each carry 10 A in the same direction. The force per metre between them i…	Physics Force on moving charges and conductors	Medium
75	A straight wire 0.5 m long carries 3 A at right angles to a uniform field of 0.4 T. The force on the wire is:	Physics Force on moving charges and conductors	Easy
76	The work done by a magnetic field on a moving charged particle is:	Physics Force on moving charges and conductors	Medium
77	A charged particle moves in a circle in a uniform magnetic field. If its speed is doubled, its time period of…	Physics Force on moving charges and conductors	Hard
78	A coil of 50 turns, each of area 0.01 m², carries 2 A. Its magnetic dipole moment is:	Physics Current loop as a magnetic dipole	Easy
79	A galvanometer of resistance 20 Ω gives full-scale deflection at 5 mA. The shunt needed to convert it into a …	Physics Current loop as a magnetic dipole	Medium
80	The same galvanometer (20 Ω, 5 mA full scale) is to be made into a 0–10 V voltmeter. The resistance to be con…	Physics Current loop as a magnetic dipole	Medium
81	A radial magnetic field is used in a moving coil galvanometer so that:	Physics Current loop as a magnetic dipole	Easy
82	A current loop is placed in a uniform magnetic field. The torque on it is maximum when:	Physics Current loop as a magnetic dipole	Hard
83	A bar magnet of moment 2 A m² is placed at 30° to a uniform field of 0.3 T. The torque on it is:	Physics Bar magnet and magnetic materials	Easy
84	Which of the following is diamagnetic?	Physics Bar magnet and magnetic materials	Easy
85	A material has magnetic susceptibility 499. Its relative permeability is:	Physics Bar magnet and magnetic materials	Medium
86	Magnetic field lines of a bar magnet:	Physics Bar magnet and magnetic materials	Medium
87	When a ferromagnetic substance is heated above its Curie temperature, it becomes:	Physics Bar magnet and magnetic materials	Hard
88	The magnetic flux through a 100-turn coil falls from 0.05 Wb to 0.01 Wb in 0.2 s. The average induced emf is:	Physics Faraday’s and Lenz’s laws	Easy
89	A rod 0.2 m long moves at 10 m/s perpendicular to a uniform field of 0.5 T. The emf across its ends is:	Physics Faraday’s and Lenz’s laws	Easy
90	Lenz’s law is a consequence of the law of conservation of:	Physics Faraday’s and Lenz’s laws	Medium
91	The SI unit of magnetic flux is:	Physics Faraday’s and Lenz’s laws	Medium
92	The cores of transformers are laminated mainly to:	Physics Faraday’s and Lenz’s laws	Hard
93	The current in a 0.2 H coil falls uniformly from 5 A to zero in 0.1 s. The average self-induced emf is:	Physics Self and mutual induction	Easy
94	The energy stored in an inductor of 0.2 H carrying 5 A is:	Physics Self and mutual induction	Easy
95	The SI unit of inductance is:	Physics Self and mutual induction	Medium
96	If the number of turns of a solenoid is doubled, keeping its length and area the same, its self-inductance be…	Physics Self and mutual induction	Medium
97	The mutual inductance between two coils does NOT depend on:	Physics Self and mutual induction	Hard
98	The peak value of an AC voltage is 325 V. Its RMS value is about:	Physics Alternating current	Easy
99	The reactance of a 0.1 H inductor at 50 Hz is about:	Physics Alternating current	Easy
100	A series LCR circuit has R = 30 Ω, X_L = 80 Ω and X_C = 40 Ω. Its impedance is:	Physics Alternating current	Medium