What is the speed of a pendulum at a given horizontal position and length?

[whatsntomake]

Homework Statement

An image of the problem may be found here:

http://i417.photobucket.com/albums/pp258/whatsntomake/Physics/Eight.png

A pendulum of length 0.950 m swings in a vertical plane (see figure). When the pendulum is in the two horizontal positions θ = 90° and θ = 270°, its speed is 4.80 m/s.

Homework Equations

A=v^2/r

The Attempt at a Solution

 

[Hootenanny]

Homework Statement

An image of the problem may be found here:

http://i417.photobucket.com/albums/pp258/whatsntomake/Physics/Eight.png

A pendulum of length 0.950 m swings in a vertical plane (see figure). When the pendulum is in the two horizontal positions θ = 90° and θ = 270°, its speed is 4.80 m/s.

Homework Equations

A=v^2/r

The Attempt at a Solution

Welcome to Physics Forums.

Be careful with your significant figures. How many significant figures does the question ask for?

 

[whatsntomake]

Hi, thanks for your quick response.
The problem does not specify any significant figure so it fine to any number of significant digits as long as the answer is close by a certain margin of error.

also I am not sure if the tangential acceleration I had is correct

 

[Hootenanny]

Hi, thanks for your quick response.
The problem does not specify any significant figure so it fine to any number of significant digits as long as the answer is close by a certain margin of error.

Okay that's fair enough.

also I am not sure if the tangential acceleration I had is correct

How did you calculate it?