Practice MCQ Questions and answers on Physics-GK Page-7 section-3

Section 1 Section 2 Section 3 Section 4 Section 5 Section 6 Section 7 Section 8 Section 9 Section 10 Section 11 Section 12 Section 13 Section 14 Section 15

61.
For which of the following substances, the resistance decreases with increase in temperature?

A. Pure silicon

B. Copper

C. Nichrome

D. Platinum

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Answer & Solution

Answer: Option B

Solution:

Option B: Copper (Correct Answer)
Copper is an exception among common conductive materials. It has a negative temperature coefficient of resistance, meaning its resistance decreases as temperature increases. This unique property makes copper an excellent conductor of electricity and well-suited for applications where minimal resistance and efficient energy transmission are required.

Option A: Pure silicon
Silicon is a semiconductor material. In semiconductors like silicon, the resistance increases with an increase in temperature. This is due to the increased thermal generation of charge carriers (electrons and holes), which increases the conductivity and resistance.

Option C: Nichrome
Nichrome is a nickel-chromium alloy commonly used as a resistance wire in heating elements. It is known for its relatively high resistivity and stability at high temperatures. However, nichrome also exhibits a positive temperature coefficient of resistance, meaning its resistance increases with temperature.

Option D: Platinum
Platinum is a metal known for its excellent resistance to corrosion and high-temperature stability. However, like most metals, platinum exhibits a positive temperature coefficient of resistance. As temperature increases, the thermal vibrations of atoms within the metal lattice increase, causing greater scattering of electrons, which in turn increases resistance.

In summary, the other options (pure silicon, nichrome, and platinum) all have materials with a positive temperature coefficient of resistance, meaning their resistance increases as temperature rises. Copper, on the other hand, exhibits a negative temperature coefficient of resistance, making it the correct choice for a substance in which resistance decreases with increasing temperature.

62.
The S.I. unit of electric charge is :

A. Ampere

B. Coulomb

C. E.s.u

D. Kelvin

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63.
Indicate the false statement about the resistance of a wire

A. It depends on material of wire

B. It is directly proportional to the length of wire

C. It is directly proportional to the area of cross-section of wire

D. Resistance of metallic wire increases with increase in temperature

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64.
The magnitude of current flowing between two end points of a conductor is proportional to the potential difference between them and is called as:

A. Avogadro's law

B. Rault's law

C. Ohms law

D. Faraday's law

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65.
What is the SI unit of electric current?

A. Newton

B. Joule

C. Ampere

D. Watt

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66.
The rate of flow of electric charge is measured in

A. Ampere

B. Coulomb

C. Ampere/coulomb

D. Ampere-coulomb

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67.
A device which is used to limit the current in an electrical circuit is called a

A. Grid

B. Fuse

C. Hub

D. Conductor

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68.
Materials that allow electricity to flow are called

A. Insulators

B. Conductors

C. Electron flows

D. Stimulators

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69.
The fundamental scientific principle in the operation of battery is

A. Acid-base interaction

B. Dialysis

C. Dissociation of electrolytes

D. Oxidation-reduction

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70.
If the current flowing through a circuit is 0.6 A for 6 mins, the amount of electric charge flowing through it is ________

A. 360C

B. 216 C

C. 60 C

D. 36 C

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Practice MCQ Questions and answers on Physics-GK

61. For which of the following substances, the resistance decreases with increase in temperature?

Answer & Solution

62. The S.I. unit of electric charge is :

Answer & Solution

63. Indicate the false statement about the resistance of a wire

Answer & Solution

64. The magnitude of current flowing between two end points of a conductor is proportional to the potential difference between them and is called as:

Answer & Solution

65. What is the SI unit of electric current?

Answer & Solution

66. The rate of flow of electric charge is measured in

Answer & Solution

67. A device which is used to limit the current in an electrical circuit is called a

Answer & Solution

68. Materials that allow electricity to flow are called

Answer & Solution

69. The fundamental scientific principle in the operation of battery is

Answer & Solution

70. If the current flowing through a circuit is 0.6 A for 6 mins, the amount of electric charge flowing through it is ________

Answer & Solution

Read More Section(Physics)

61.
For which of the following substances, the resistance decreases with increase in temperature?

62.
The S.I. unit of electric charge is :

63.
Indicate the false statement about the resistance of a wire

64.
The magnitude of current flowing between two end points of a conductor is proportional to the potential difference between them and is called as:

65.
What is the SI unit of electric current?

66.
The rate of flow of electric charge is measured in

67.
A device which is used to limit the current in an electrical circuit is called a

68.
Materials that allow electricity to flow are called

69.
The fundamental scientific principle in the operation of battery is

70.
If the current flowing through a circuit is 0.6 A for 6 mins, the amount of electric charge flowing through it is ________