A particle is in uniform circular motion. Assume a standard rtz coordinate system. If you deconstruct the net force acting on the particle along each of these axes (r (radial), t (tangential), and z (perpendicular to the plane of motion), how many non-zero force components exist?

a) One
b) Two
c) Three
d) Zero - There is no net force on a particle in uniform circular motion

a) One

Explanation:

In a uniform circular motion there must be a force acting to keep it in the circular track. This force can either be centripetal or a centrifugal force.

According to the Newton's first law of motion a particle continues to be in state of rest or in uniform motion until acted upon by an external force.

Here the term uniform motion need to be understood which refers to the uniform velocity of the particle in accordance to the vector laws.

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