Final answer:
The claim that a coin rotating on a turntable moves without sliding is generally false because static friction is needed to prevent slipping. If the static friction is not sufficient, the coin will begin to slide.
Step-by-step explanation:
You asked if a coin rotating on a turntable would move without sliding. The answer to this is generally false. When a coin is rotating on a turntable, there is often some frictional force acting between the coin and the surface of the turntable. This friction is necessary for the coin to rotate without slipping. If this frictional force, known as static friction, is not enough to prevent the relative motion between the turntable and the coin, the coin will start to slip or slide. An example of this is when you place a coin flat on a book and tilt it until the coin slides at a constant velocity down the book. This demonstrates that a coin can move with sliding if the static friction is overcome by the force of gravity acting on the coin.
In physics demonstrations, such as the one where a professor places two coins on the edge of a table and flicks one while nudging the other, both coins hit the ground at the same time. This is because the motion in the horizontal direction does not affect the falling motion due to gravity. However, this scenario is about coins falling and not rotating on surfaces, which is a different context from the turntable situation.