Explanation :
A ball is rolled along the inside of a partial hoop lying flat on a table. The ball will move in a straight path as shown in the attached figure.
The figure shows a semicircular hoop. When the ball reaches at the other end, it will move tangentially.
In a circular path, the object move with constant speed but the velocity changes at every instant.
So, the ball will move in a straight line when it reaches at the end of the hoop.