Block 1 is at rest on a horizontal surface and is connected to a wall by an ideal spring. Friction between block 1 and the surface is negligible. Block 1 is held at rest at point A. released from point \( A \) and allowed to oscillate. Later, block 1 is momentarily at rest at point C. Consider the positive horizontal direction to be toward the right as shown in the figure above. (a) The dot below represents block 1 . i. On the dot below to the left, draw an arrow indicating the direction of the net force exerted on the block just after it has been released at point A. On the dot below to the right, draw an arrow indicating the direction of the net force exerted on the block when it has reached Point C. Any arrows draw should start on, and point away from, the dot. if

When the block is at a turning point the only horizontal force acting on it (since friction is negligible) is the spring’s restoring force. Since a spring always pulls (or pushes) the block back toward its equilibrium position, the net force at a turning point points from the block’s extreme position back toward equilibrium. In this problem the spring is connected to a wall. (Typically the wall is on the left, but the key point is that the equilibrium position lies between the two extreme positions labeled A and C.) Thus: • At point A the block is at one extreme (say, the leftmost position) so the equilibrium lies to its right. Therefore, just after release from A, the net force on the block is directed to the right (i.e. in the positive x‑direction). • At point C the block has reached the opposite extreme (the rightmost position), so the equilibrium lies to its left. At this moment the net force (again, the spring’s restoring force) is directed to the left (i.e. the negative x‑direction). When drawing your arrows: – On the dot for point A, draw a short arrow that starts at the dot and points to the right. – On the dot for point C, draw a short arrow that starts at the dot and points to the left. This correctly represents the directions of the net force on the block at points A and C.