Posted by Brianna on Wednesday, November 10, 2010 at 1:47pm.
A child swings a yoyo of weight mg in a horizontal circle so that the cord makes an angle of 30 degrees with the vertical. Find the centripetal acceleration.

College Physics  bobpursley, Wednesday, November 10, 2010 at 1:52pm
Ok, the radius of rotation is length*sin30 where length is the length of string.
looking at vectors, mg is down, and mv^2/r is outward, so tan30=mv^2/(r*mg)
tan 30= v^2/(length*sin30*g)
but v= 2PI(length*sin30) square that, put it in the equation
tan30=4PI^2*length*sin30/g check that. solve for length of string.
finally, centacc= v^2/r and you can do that algebra.

College Physics  drwls, Wednesday, November 10, 2010 at 1:55pm
You did not say what the mass M is. As turns out, you don't need to know M to get the answer. First convert the mass to weight, W.
W = Mg
The vertical component of string tension is T cos30 = Mg
The horizontal component of string tension is the centripetal force
T sin30 = Ma,
where a is the centripetal acceleration
Divide one by the other and you get
sin30/cos30 = tan30 = sqrt3 = a/g
Solve for a.
Answer This Question
Related Questions
 Physics  A model airplane is flying in a horizontal circle with a constant ...
 Physics  A model airplane is flying in a horizontal circle with a constant ...
 Physics  a small body of mass m revolving in a horizontal circle with velocity ...
 Physics  A sphere of mass 3.0X10^4 kg is suspended from a cord. A steady ...
 physics  One end of a cord is fixed and a small 0.610 kg object is attached to ...
 Physics/Math  A sphere of mass 2.7 x 10^4 kg is suspended from a cord. A ...
 Physics  An aerialist on a high platform holds onto a trapeze attached to a ...
 PHYSICS  An aerialist on a high platform holds onto a trapeze attached to a ...
 Physics  An aerialist on a high platform holds onto a trapeze attached to a ...
 Science  A father swings his child around in a circle. The source of the ...
More Related Questions