Finding angular acceleration from deceleration

In summary, angular acceleration is the measure of how quickly an object's rotational speed is changing. It is related to deceleration as they are essentially the same concept with opposite signs. To calculate angular acceleration from deceleration, you can use the formula a = (vf - vi) / t, where a is the angular acceleration, vf is the final angular velocity, vi is the initial angular velocity, and t is the time interval. The units of angular acceleration are radians per second squared (rad/s²), which is the ratio of radians per second and seconds. Angular acceleration can be negative, indicating deceleration, or positive, indicating acceleration.
  • #1
Sneakatone
318
0
a-c are correct but I don't know how to find part d.

d)when turned off, it decelerates to a stop in 39s. What is its average angular acceleration during this time?

I treated this part as part c to just find angular acceleration like normal.
371.75 rad/s / 39s=9.51 rad/s^2.
should it be negative because it decelerates?
 

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  • #2
Sneakatone said:
should it be negative because it decelerates?

Yep!

Angular acceleration is defined as (change in angular speed)/(change in time). The speed goes from 371 rad/s to 0, that gives you a negative number.
 
  • #3
Oh wow. Thanks!
 

Related to Finding angular acceleration from deceleration

1. What is angular acceleration?

Angular acceleration is the rate of change of angular velocity with respect to time. It is a measure of how quickly an object's rotational speed is changing.

2. How is angular acceleration related to deceleration?

Angular acceleration and deceleration are essentially the same concept, but with opposite signs. Angular acceleration refers to an increase in rotational speed, while deceleration refers to a decrease in rotational speed.

3. How can I calculate angular acceleration from deceleration?

To calculate angular acceleration from deceleration, you can use the formula a = (vf - vi) / t, where a is the angular acceleration, vf is the final angular velocity, vi is the initial angular velocity, and t is the time interval. Make sure to use the appropriate units for angular velocity (radians per second) and time (seconds).

4. What are the units of angular acceleration?

The units of angular acceleration are radians per second squared (rad/s²). This is because angular velocity is measured in radians per second, and time is measured in seconds, so the ratio of the two would be radians per second squared.

5. Can angular acceleration be negative?

Yes, angular acceleration can be negative. This indicates that the object is decelerating, or slowing down its rotational speed. A positive angular acceleration indicates that the object is accelerating, or increasing its rotational speed.

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