A fan initially rotating at 60 rad/sec clockwise accelerates and acquires an angular velocity of 110 rad/sec clockwise. If the angular acceleration of the fan is constant and it takes 2 sec to change its angular velocity, find the angular acceleration of the fan. A. 50 rad/sec2 in counterclockwise direction B. 25 rad/sec2 in counterclockwise direction C. 25 rad/sec2 in clockwise direction D. 50 rad/sec2 in clockwise direction

Collegedunia Team

Content Curator

The correct option is (C)

The equation of rotational motion for constant angular acceleration is given by

ω_f = ω_i + αt

⇒ α = $\frac{\omega_f - \omega_i}{t}$

Where,

ω_f = final angular velocity
ω_i = initial angular velocity
α = angular acceleration
t = time taken to reach final angular velocity from initial angular velocity.

Taking the clockwise direction as -ve and counterclockwise as +ve.

Given,

Initial angular velocity of the fan, ω_i = – 60 rad/s

final angular velocity of the fan, ω_f = – 110 rad/s

Time taken, t = 2 sec

Using the equation of rotational motion, angular acceleration (α) of the fan, is given by

α = $\frac{(-110)-(-60)}{2}$ = – $\frac{50}{2}$

⇒ α = – 25 rad/sec²

Negative sign shows that the angular acceleration of the fan is in the clockwise direction.

Hence, the angular acceleration of the fan is 25 rad/sec² in clockwise direction.

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A fan initially rotating at 60 rad/sec clockwise accelerates and acquires an angular velocity of 110 rad/sec clockwise. If the angular acceleration of the fan is constant and it takes 2 sec to change its angular velocity, find the angular acceleration.

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A fan initially rotating at 60 rad/sec clockwise accelerates and acquires an angular velocity of 110 rad/sec clockwise. If the angular acceleration of the fan is constant and it takes 2 sec to change its angular velocity, find the angular acceleration.

CBSE CLASS XII Related Questions

1.Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air present between the plates.

2.Two metal spheres of radii $r_1$ and $r_2$ ($> r_1$) having charges $q_1$ and $q_2$ respectively kept in air, are brought in contact. Which of the following statements is not correct ?

4.Write two advantages of reflecting telescope over refracting telescope.

6.With the help of a labelled diagram, explain the principle, construction and working of an a.c. generator.

Similar Physics Concepts

Comments

SUBSCRIBE TO OUR NEWS LETTER

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Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air present between the plates.

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4.
Write two advantages of reflecting telescope over refracting telescope.

6.
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