# Calculating Speed of a motion of a Circular Object

1. Jan 22, 2009

### Jordash

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

A conical pendulum is made of a ball on the end of a string, moving in circular motion as represented in the ﬁgure below. The length L of the string is 1.70 m, the angle θ is 37.0o, and the ball completes one revolution every 2.30 s.

Calculate the speed of the ball, by ﬁrst deriving a symbolic equation and then inserting the
numbers.

2. Relevant equations

3. The attempt at a solution

I sort of know how to do this problem without the degrees.

2. Jan 22, 2009

### LowlyPion

I can't see the picture, but I presume that it is rotating in a horizontal plane.

First of all you know that the ball is describing a circle that has a radius of L*Sin37°.

You know the time to complete a revolution ...

3. Jan 24, 2009

### Jordash

Alright, here is what I got

R=L*sin(37)

R=1
Diameter=2
Circumference=pi(2)

Circumference=6.3

Speed=Distance Traveled/Time

Speed=6.3m/2.3s

= 2.7m/s

Is that right?

4. Jan 24, 2009