One end of a cord is fixed and a small 0.470-kg object is attached to the other end, where it swings in a section of a vertical circle of radius 2.50 m as shown in the figure below. When θ = 21.0°, the speed of the object is 4.70 m/s. At this instant, find each of the following.

Question

(a) the tension in the string

(b) the tangential and radial components of acceleration

(c) the total acceleration

I have the tension and it is 8.48N and I have the radial component of acceleration. I can't figure out how to get the tangential component of acceleration.

Please help and thank you.

bobpursley · Answer

Tangential acceleration is due to gravity. So you are looking for the component of gravity in the direction of the tangent.

tangential acceleration= g*sinorcosine 21

I don't know how your angle is measured, but you will need sin21 or cos21. Draw the figure.

Cody · Answer

Thank you very much. I used sin21 and it was right.