A disc of radius r and carrying positive charge q is rotating with an angular speed w in a uniform magnetic field B about a fixed axces as shown in figure such that angle made by the axis of disc with magnetic field is alpha. torque applied by the axis on the disc is?

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A disc of radius r and carrying positive charge q is rotating with an angular speed w in a uniform magnetic field B about a fixed axces as shown in figure such that angle made by the axis of disc with magnetic field is alpha. torque applied by the axis on the disc is?

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A disc of radius r and carrying positive charge q is rotating with an ...

Torque on a rotating disc in a magnetic field

The torque applied by the axis on the rotating disc can be calculated using the formula:

Torque (τ) = Magnetic field (B) × Area (A) × Angle (θ) × Sin(α)

Where:
- Magnetic field (B) is the strength of the magnetic field in Tesla.
- Area (A) is the area of the disc in square meters.
- Angle (θ) is the angle between the magnetic field and the normal to the disc's surface.
- Sin(α) is the sine of the angle made by the axis of the disc with the magnetic field.

Explanation:
To understand this formula, let's break down the components:

Magnetic field (B):
The magnetic field is a region in which a magnetic force can be detected. In this case, the disc is rotating in a uniform magnetic field.

Area (A):
The area of the disc is given by the formula A = πr^2, where r is the radius of the disc.

Angle (θ):
The angle θ is the angle between the magnetic field and the normal to the disc's surface. Since the disc is rotating about a fixed axis, the axis is perpendicular to the disc's surface, making the angle θ equal to 90 degrees.

Sin(α):
Sin(α) is the sine of the angle made by the axis of the disc with the magnetic field. This angle is denoted by α in the figure.

Torque (τ):
The torque applied on the disc is given by the formula τ = B × A × θ × Sin(α). As we know, the torque is a measure of the rotational force applied to an object. In this case, the torque represents the force exerted by the magnetic field on the rotating disc.

So, the torque applied by the axis on the disc is given by the formula τ = B × πr^2 × 90 × Sin(α).

Note: The direction of the torque can be determined using the right-hand rule, where the thumb points in the direction of the magnetic field, the fingers point in the direction of the current or motion, and the palm gives the direction of the torque.

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A disc of radius r and carrying positive charge q is rotating with an angular speed w in a uniform magnetic field B about a fixed axces as shown in figure such that angle made by the axis of disc with magnetic field is alpha. torque applied by the axis on the disc is? for Class 12 2024 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about A disc of radius r and carrying positive charge q is rotating with an angular speed w in a uniform magnetic field B about a fixed axces as shown in figure such that angle made by the axis of disc with magnetic field is alpha. torque applied by the axis on the disc is? covers all topics & solutions for Class 12 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A disc of radius r and carrying positive charge q is rotating with an angular speed w in a uniform magnetic field B about a fixed axces as shown in figure such that angle made by the axis of disc with magnetic field is alpha. torque applied by the axis on the disc is?.

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