# Homework Help: Tension in an object moving with circular motion

1. Sep 20, 2016

### Nat Reed

1. The problem statement, all variables and given/known data
An object of mass 0.8kg is whirled round in a horizontal circle of radius 2m with a constant speed of 15ms-1. Calculate the tension in the string.

3. The attempt at a solution
So far I have calculated that the angular velocity is 7.5rads-1, the frequency is 1.19Hz and the time period is 0.84s, I'm just not sure where to go from here.

2. Sep 20, 2016

### billy_joule

Where did the relevant equations section go?
You didn't need to find angular velocity, frequency or period.
There is a single equation you can use to find tension from the given variables.

3. Sep 20, 2016

### Staff: Mentor

Have you drawn a free body diagram? Do you know an equation for calculating the acceleration of the object?

4. Sep 20, 2016

### Kaura

Looks like you have everything you need in terms of variables
See if there is an equation that can use these variables to calculate centripetal acceleration

5. Sep 20, 2016

### Ankush GK

Draw the FBD and analyse the forces acting on the body.

Then frame an eqn. of horizontal and vertical eqbm.
U can get the required ans

6. Sep 21, 2016

### Nat Reed

Thank you very much for the help everyone!

7. Dec 13, 2016

### darmzynyolarh

Plz i nid formula to dat first question

8. Dec 13, 2016

### Staff: Mentor

What are your thoughts on this so far? Can you say in words what is happening physically in this problem?