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Circular Logic - help13

Velocity is a vector that is fully described by a numerical value (such as 20 m/s) and a direction. Objects that move along a circular path have a velocity vector that is directed tangent to the path. Such objects are also experiencing an acceleration and a net force. Acceleration and net force are both vector quantities that have a direction that is towards the center of the circle.

There are three similar versions of this question. Here is one of those versions:

Version 1:

An object is moving clockwise around the circle. Identify the direction of the velocity vector at D and the acceleration vector at H and the net force vector at A.

Velocity Vector

You have three tasks. One task involves determining the direction of the velocity vector. You can tap on the Change button to toggle through all eight options. You're looking for the one option that is in the direction of motion and tangent to the circle. In describing the velocity vector as being tangent, we are saying that it is in a direction that, if extended, would only touch the circle at only one location. You will find two such tangential vectors. Pick the one that is in the direction of motion - clockwise. The small arced arrow displayed inside of the circle shows which way clockwise is.

Acceleration Vector

Your second task involves determining the direction of the acceleration vector. You can tap on the other Change button to toggle through all eight options. You're looking for the one option that displays a vector pointing towards the circle's center. This is the inwards or centripetal acceleration.

Net Force Vector

Your third task involves determining the direction of the net force vector. You can tap on the other Change button to toggle through all eight options. You're looking for the one option that displays a vector pointing towards the circle's center. This is the inwards or centripetal net force.

Try these links to The Physics Classroom Tutorial for more help with the direction of the velocity, acceleration and net force vectors:

Speed and Velocity

Acceleration

Centripetal Force Requirement