When the radial acceleration is zero and the tangential acceleration is non-zero, the motion can be uniform or variable depending on the specific conditions. Let's explore both scenarios:
Uniform Motion: If the tangential acceleration is constant (non-zero) and the radial acceleration is zero, it means that the object is moving along a circular path at a constant speed. In this case, the motion is uniform because the object maintains a constant tangential velocity. Although the object is changing direction, the magnitude of its velocity remains constant.
Variable Motion: If the tangential acceleration is changing (non-zero) and the radial acceleration is zero, the motion is variable. In this situation, the object is still moving along a circular path, but its speed is changing. The object's velocity is not constant because the tangential acceleration affects its magnitude. As a result, the object's motion is variable.
In summary, when the radial acceleration is zero and the tangential acceleration is non-zero, the motion can be uniform if the tangential acceleration is constant, or variable if the tangential acceleration is changing.