A copper wire of 10 - 6 m 2 , area of cross section, carries a current of 2 A , If the no of electrons per cubic meter is 8 × 10 28 , Calculate the current density and average drift velocity.

Given, The area of cross section, A = 10 - 6 m 2 The current in the wire, I = 2 A The number of electrons per cubic meter, n = 8 × 10 28 We know, Current density, J = I A = 2 10 - 6 = 2 × 10 6 A / m 2 The relation between current and the average drift velocity ( V d ) is given by, I = n e A V d ⇒ 2 = 8 × 10 28 × 1 . 6 × 10 - 19 × 10 - 6 × V d ⇒ V d = 2 8 × 1 . 6 × 10 3 = 15 . 6 × 10 - 5 m / s

A copper wire of 10 - 6 m 2 , area of cross section, carries a current of 2 A , If the no of electrons per cubic meter is 8 × 10 28 , Calculate the current density and average drift velocity.

Given, The area of cross section, A = 10 - 6 m 2 The current in the wire, I = 2 A The number of electrons per cubic meter, n = 8 × 10 28 We know, Current density, J = I A = 2 10 - 6 = 2 × 10 6 A / m 2 The relation between current and the average drift velocity ( V d ) is given by, I = n e A V d ⇒ 2 = 8 × 10 28 × 1 . 6 × 10 - 19 × 10 - 6 × V d ⇒ V d = 2 8 × 1 . 6 × 10 3 = 15 . 6 × 10 - 5 m / s

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A copper wire of $10^{- 6} m^{2}$ , area of cross section, carries a current of $2 A$ , If the no of electrons per cubic meter is $8 \times 10^{28}$ , Calculate the current density and average drift velocity.

Important Questions on Solved Physics Paper-2

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 16 - Ray Optics and Optical Instruments>Exercise>Q 33

Use the mirror equation to deduce that:
A convex mirror always produces a virtual image independent of the location of the object.
[Note: This exercise helps you deduce algebraically properties of images that one obtains from explicit ray diagrams.]

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 16 - Solved Physics Paper-2>Exercise>Q 20

A square coil of side

10 cm

and

20

turns have a current

12 A

is suspended vertically. If its area vector makes an angle

30 °

with uniform magnetic field of

0.08 T

. Find the torque on the coil.

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 16 - Solved Physics Paper-2>Exercise>Q 21

A parallel plate capacitor is kept at a certain potential difference. Keeping this potential difference constant to put a dielectric slab of

3 mm

thickness between the plates, the plate separation is to be increased by

2.4 mm

. Calculate the dielectric constant of slab.

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 16 - Solved Physics Paper-2>Exercise>Q 22

With the help of schematic sketch of a cyclotron, explain its working principle. Mention its two applications. What is the important limitation encountered in accelerating a light elementary particle such as electron to high energies?

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 16 - Solved Physics Paper-2>Exercise>Q 23

What is the nature of electromagnetic wave? Explain the Hertz's experiment related to electromagnetic wave.

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 16 - Solved Physics Paper-2>Exercise>Q 24

Obtain an expression for the frequency of radiation emitted when a hydrogen atom de-excites from level

n

to level

(n - 1)

. For large

n

, show that this frequency equals the classical frequency of revolution of the electron in the orbit.

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 16 - Solved Physics Paper-2>Exercise>Q 25

Write down the boolean expression for given logic circuit. And also write truth table for it.

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 16 - Solved Physics Paper-2>Exercise>Q 26

The wires which connect the battery of an automobile to its starting motor carry a current of

300 A

(for a short time). What is the force per unit length between the wires if they are

70 cm

long and

1 \cdot 5 cm

apart? Is the force attractive or repulsive?

A copper wire of 10-6 m2, area of cross section, carries a current of 2 A, If the no of electrons per cubic meter is 8×1028, Calculate the current density and average drift velocity.

Important Questions on Solved Physics Paper-2

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A copper wire of $10^{- 6} m^{2}$ , area of cross section, carries a current of $2 A$ , If the no of electrons per cubic meter is $8 \times 10^{28}$ , Calculate the current density and average drift velocity.