What does Dr. Hewitt do to drag the block across the table at a steady rate?

To maintain a steady rate when dragging the block across the table, Dr. Hewitt must apply a steady force that is equal to the opposing forces acting on the block, such as friction. When an object moves at a constant velocity, according to Newton's first law of motion, the net force acting on it must be zero. In this case, the applied force must balance out the frictional force resisting the motion.

If Dr. Hewitt applies a steady force, it provides the necessary impetus to keep the block moving uniformly without acceleration or deceleration. This relationship illustrates the principle of equilibrium in mechanics: the forces are balanced when the velocity remains constant.

For instance, stopping the application of force would result in the block slowing down due to friction. Gradually increasing the force would cause the block to accelerate, while gradually decreasing the force would lead it to slow down as well. Thus, the only way for Dr. Hewitt to drag the block at a consistent speed is by applying a steady force that counteracts friction, confirming that applying a steady force is the correct method in this scenario.