Solving Circular Motion Problems: Finding Acceleration and Force

AI Thread Summary
To solve the circular motion problem involving a 4.0 kg ball on a 0.70 m string spinning at 2.0 m/s, the centripetal acceleration can be calculated using the formula a = v²/r. This results in a centripetal acceleration of approximately 5.71 m/s². To find the centripetal force, use Newton's Second Law, F = ma, which gives a force of about 22.84 N. A free body diagram is recommended for better visualization of the forces involved. Following these steps will lead to the correct answers for both acceleration and force.
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Circular Motion HW Help!

Homework Statement


Problem: A 4.0kg ball is attached to 0.70m string and spun at 2.0m/s. Calculate the centripetal acceleration of the ball and the centripetal force on the ball.

Homework Equations


I don't know of any other ones our teacher gave us some worksheets and this is the only one like this !



The Attempt at a Solution


[a][/c]=[v][/2]



Homework Equations





The Attempt at a Solution

 
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Hi. This is a relatively simple problem (hence, I can help you solve it).

First piece of advice, always draw a fbd (free body diagram). It helps to clarify things, and gives you something to visualize.

Here, you know that the centripetal force is a center seeking force, and the velocity is always tangent to the circle.

Did you learn an equation in class today, that relates the two values of velocity and radius, to find the centripetal acceleration?

After you find the acceleration, remember Newton's Second law. F=ma. Once you know acceleration, you can find the centripetal (center seeking) force.

Try it!
 


yes but do you know what equation I need to use?
 


how do i find acceleration?
 


Centripetal (Radial) acceleration = (velocity^2)/radius
Centripetal force = mass*centripetal acceleration

plug the numbers in and you should get the answer.
 
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