Practice

Question 101

Lenz’s law is a consequence of the conservation of

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Correct answer: (A) Energy

1 marks · 2023 · Set A

Question 102

Mobility is denoted by

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Correct answer: (C) μ

1 marks · 2023 · Set A

Question 103

If E and B are electric and magnetic fields, respectively, which quantity is dimensionless?

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Correct answer: (A) √(μ₀ε₀) E/B

1 marks · 2023 · Set A

Question 104

Which of the following is a non-ohmic resistance?

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Correct answer: (B) Diode

1 marks · 2023 · Set A

Question 105

When the diameter of the objective aperture of an astronomical telescope increases, its

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Correct answer: (B) Magnifying power remains unchanged but resolving power increases

1 marks · 2023 · Set A

Question 106

The magnetic field lines passing through the centre of a current-carrying circular loop are

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Correct answer: (C) Straight lines

1 marks · 2023 · Set A

Question 107

Conduction current is the same as displacement current when the source is

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Correct answer: (A) A.C. only

1 marks · 2023 · Set A

Question 108

The light energy emitted by a star is due to

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Correct answer: (A) Joining of nuclei

1 marks · 2023 · Set A

Question 109

In a diffraction pattern, the fringe width is

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Correct answer: (C) Inversely proportional to slit width

1 marks · 2023 · Set A

Question 110

What happens to the quality factor of an L-C-R circuit if its resistance is increased?

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Correct answer: (B) Decreases

1 marks · 2023 · Set A

Question 111

What is the de Broglie wavelength of neutrons in thermal equilibrium with matter at 300 K?

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Correct answer: (B) 1.79 Å

1 marks · 2023 · Set A

Question 112

When is the current in a circuit wattless?

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Correct answer: (B) When the circuit’s resistance is zero

1 marks · 2023 · Set A

Question 113

Photoelectric emission can be explained by the

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Correct answer: (B) Particle nature of light

1 marks · 2023 · Set A

Question 114

Which microwave component uses the principle of Faraday rotation?

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Correct answer: (D) More than one of the above

1 marks · 2023 · Set A

Question 115

A proton and an electron are accelerated through the same potential difference. Their de Broglie wavelengths λe and λp are such that

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Correct answer: (B) λe > λp

1 marks · 2023 · Set A

Question 116

Many thin strips of black paint are made on a convex lens of focal length 20 cm to image a white horse. The image will be

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Correct answer: (A) A horse of lower brightness

1 marks · 2023 · Set A

Question 117

The total energy of an electron in the nth orbit of a hydrogen atom is

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Correct answer: (B) −e²/(8πε₀rₙ)

1 marks · 2023 · Set A

Question 118

The emission of electrons from a metal surface when radiation of an appropriate frequency falls on it is called

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Correct answer: (C) Photoelectric effect

1 marks · 2023 · Set A

Question 119

During a nuclear fission reaction

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Correct answer: (B) A heavy nucleus bombarded by thermal neutrons breaks up

1 marks · 2023 · Set A

Question 120

In nuclear reactions, which quantity is conserved?

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Correct answer: (D) More than one of the above

1 marks · 2023 · Set A

TRE1 — General Studies And Physics