Accelerometer via ball on string

AI Thread Summary
To measure forward acceleration using a free-swinging ball on a string, one must consider the forces acting on the ball, including gravitational force and tension in the rope. A free body diagram can help visualize these forces. By applying Newton's second law, the net force can be computed vectorially. The relationship between acceleration (a) and the angle (theta) of the string with the vertical can be expressed as tan(theta) = a/g. This equation confirms the connection between the angle and the acceleration due to gravity.
andrewr0x
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How would I go about measuring forward acceleration using a free-swinging ball on a stand? Could anyone post a free body diagram or an equation that might describe this?
 
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Two external forces on the ball:
downward gravitational force with magnitude (mg)
tension tangent to the the rope (T)

Compute net-force vectorially.

Use Netwon II.
Solve for the acceleration (a) as a function of angle (theta) with respect to the vertical.
 
Would tan(theta)=a/g ?
 
andrewr0x said:
Would tan(theta)=a/g ?
That's right. (Where theta is the angle the string makes with the vertical.)
 
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