To determine during which step the robotic arm does work on the block, we should understand what "doing work" entails in a physics context. Work is done when a force causes an object to move in the direction of the force.
Let's analyze each step:
1. Step 1: Grip block.
- In this step, the robotic arm grips the block. Gripping involves applying force to hold the block but does not involve movement of the block in the direction of the force applied.
2. Step 2: Lift block ten centimeters.
- Here, the robotic arm lifts the block ten centimeters. Lifting the block requires exerting an upward force against gravity, and the block moves in the direction of the applied force (upward). Therefore, work is done on the block during this step.
3. Step 3: Hold for twenty seconds.
- Holding the block in place involves applying a force to counteract gravity, but since there is no movement of the block, no work is done during this step.
4. Step 4: Release block.
- In this step, the robotic arm releases the block. Releasing may involve ceasing to apply force, but it does not involve applying a force that causes movement in the same way that lifting does.
Based on this analysis, we can conclude that the robotic arm does work on the block during Step 2, when it lifts the block ten centimeters. Thus, the correct step is:
Step 2
