# Homework Help: Centripetal Acceleration of washer spin cycle

1. Oct 7, 2007

### CursedAntagonis

1. The problem statement, all variables and given/known data

On your first day at work for an appliance manufacturer, you are told to figure out what to do to the period of rotation during a washer spin cycle to triple the centripetal acceleration. You impress your boss by answering immediately.

2. Relevant equations

a=(4pi^2R)/T^2

3. The attempt at a solution

I read the question, and I keep thinking they just want to triple the accleration...which is not the answer. I don't exactly know what they are asking for....

2. Oct 7, 2007

### Kurdt

Staff Emeritus
Using that equation is a bit nasty since T is squared. You can tidy it up by remembering that $R=v^2/a$. So once you have your equation You pretty much have your answer since you know how the two quantities are related. When one triples the other _______.

3. Oct 7, 2007

### CursedAntagonis

This is part of an online homework and the program keeps telling me I am getting the wrong answer.

It wants the answer in terms of T and I cannot have variables a, v, R or pi in there. I must be making an exteremely dumb mistake......

4. Oct 7, 2007

### Kurdt

Staff Emeritus
If I said a was proportional to the inverse of T, that is:

$$a \propto \frac{1}{T}$$

The you you want 3 x a, what will the above proportionality be? That is what would be done to T to make a 3 times larger?

5. Jan 30, 2008

### Kurdt

Staff Emeritus
Why have you bumped this thread?

6. Jan 30, 2008

### treverd

So does anyone have an idea what the answer is?

I have this same question and for the answer they have it setup as

T^3=_____________

Thanks

7. Jan 30, 2008

### Kurdt

Staff Emeritus
We don't provide the answers for you here. You have to show some of your own work.

8. Jan 31, 2008

### blindside

Try an algebraic approach if you can't get it by thinking about it.

$$3a = 3\left[\frac{4\pi^2R}{T^2}\right]$$

Now get rid of the 3 on the RHS by determining a coefficient for T within the square.

9. Jan 31, 2008

### treverd

Thank you BlindSide Youve been a great help.