Ten seconds after an electric fan is turned on, the fan rotates at 300 rev/min. Its average angular acceleration is
Correct answer: C. 30 rev/s²
- A. 30 rad/s²
- B. 3.14 rad/s²
- C. 30 rev/s²
- D. 500 rev/s²
Explanation
Formula for average angular acceleration: As before, we use the formula:α = (ω₂ - ω₁)/(t₂ - t₁)Converting RPM to rad/s: 300 rev/min is equal to 300 x 2π/60 rev/s (approximately 50 rev/s).Plugging in values: Since the fan starts from rest (ω₁ = 0), we have:α = (50 - 0) / (10 - 0) = 50 / 10 = 5 rev/s²Therefore, the average angular acceleration is 5 re/s².
Last updated
About Angular Velocity
Angular velocity describes how quickly angular displacement changes with time, with ω = Δθ/Δt and units of radians per second. Questions relate angular and linear motion through v = rω, use the direction given by the right hand rule, and distinguish angular velocity from angular acceleration and ordinary frequency.
Practise Rotational and Circular Motion
521 free Rotational and Circular Motion MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 13 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
A body moves with constant angular velocity on a circle. Magnitude of angular acceleration is:
A body moving in a circle at constant speed
A body performing circular motion with a constant speed has a constant:
A fly wheel rotates at a constant speed of 3000rpm. The angle described by the shaft in radian in one second is:
A flywheel gains a speed of 540 rpm in 6 seconds. Its angular acceleration is: