# Angular deceleration of a washing machine spin cycle

• Zoubayr
In summary, the conversation discusses calculating the angular acceleration and time for a washing machine during the rapid spin-dry cycle, given initial angular speed and stopping distance. The formula w^2=(w_0)^2+2αθ is used to find the angular acceleration, and the formula w=w_o+αt is used to find the time. The units for angles in rotational dynamics are typically measured in radians.
Zoubayr
Homework Statement
If you lift the lid of a washing machine during the rapid
spin–dry cycle, the cycle stops (for safety), typically after 5.0
revolutions. If the clothes are spinning at 6.0 rev/s initially,
what is their constant angular acceleration during the slowing
motion? How long do they take to come to a stop?
Relevant Equations
w=w_o+αt
6.0 rev - 1 s
1 rev - 1/6
5.0 rev - (1/6) x 5 = (5/6) s = 0.833 s

I do not know how to calculate the angular acceleration

Zoubayr said:
Homework Statement:: If you lift the lid of a washing machine during the rapid
spin–dry cycle, the cycle stops (for safety), typically after 5.0
revolutions. If the clothes are spinning at 6.0 rev/s initially,
what is their constant angular acceleration during the slowing
motion? How long do they take to come to a stop?
Relevant Equations:: w=w_o+αt

6.0 rev - 1 s
1 rev - 1/6
5.0 rev - (1/6) x 5 = (5/6) s = 0.833 s

I do not know how to calculate the angular acceleration
You need a second equation since you are looking to solve two unknowns, ##\alpha## and ##t##. They give you a hint by giving you the stopping distance ##\theta##.

There is another equation relating angular speeds, angular acceleration and total angle. That equation does not have time in it.

malawi_glenn said:
There is another equation relating angular speeds, angular acceleration and total angle. That equation does not have time in it.
w^2=(w_0)^2+2αθ
how to know the total angle θ?

Zoubayr said:
w^2=(w_0)^2+2αθ
how to know the total angle θ?
The angle is given. It is 5 revolutions.

malawi_glenn
bob012345 said:
The angle is given. It is 5 revolutions.
so by using the formula: w^2=(w_0)^2+2αθ with w_0 being 6.0 rev/s, w being zero and θ being 5 we get the answer?

Zoubayr said:
so by using the formula: w^2=(w_0)^2+2αθ with w_0 being 6.0 rev/s, w being zero and θ being 5 we get the answer?
One of the answers. How do you get the time next?

bob012345 said:
One of the answers. How do you get the time next?
using this equation: w=w_o+αt with w_0 being 6.0 rev/s, w being zero and α being the value calculated from the 1st part of the question.

bob012345
Zoubayr said:
using this equation: w=w_o+αt with w_0 being 6.0 rev/s, w being zero and α being the value calculated from the 1st part of the question.
Note that the acceleration is a negative number from the first part giving the time as a positive number in the second part which is good.

Zoubayr said:
and θ being 5 we get the answer?
What units do we measure angles with in the context of rotational dynamics?

## 1. What is angular deceleration?

Angular deceleration is the rate at which the angular velocity of an object decreases over time. It is typically measured in radians per second squared (rad/s^2).

## 2. How does angular deceleration affect a washing machine spin cycle?

In a washing machine spin cycle, the angular deceleration determines how quickly the drum slows down and comes to a stop. A higher angular deceleration means the drum will slow down more quickly, while a lower angular deceleration will result in a slower deceleration.

## 3. What factors can affect the angular deceleration of a washing machine spin cycle?

The main factors that can affect the angular deceleration of a washing machine spin cycle include the mass of the drum, the speed at which it is spinning, and any external forces acting on the drum (such as friction or air resistance).

## 4. Can the angular deceleration of a washing machine spin cycle be controlled?

Yes, the angular deceleration of a washing machine spin cycle can be controlled by adjusting the settings on the machine. For example, changing the spin speed or load size can affect the angular deceleration.

## 5. Why is it important to understand the angular deceleration of a washing machine spin cycle?

Understanding the angular deceleration of a washing machine spin cycle can help us optimize the efficiency and performance of the machine. It can also help us troubleshoot any issues that may arise during the spin cycle.

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