Work equals force times distance for constant force

Steps:

• Identify the formula for work done by a constant force: W = F × d, where F is force and d is displacement in the direction of force.
• Note the given values: force F = 20 N, length of tape (displacement) d = 50 m.
• Calculate: W = 20 N × 50 m = 1000 J.
• Confirm units: newtons times meters yield joules.

Why D is correct:

• Work is defined as the product of constant force and displacement parallel to the force (W = Fd).

Why the others are wrong:

• A: Assumes no displacement, but tape unwraps 50 m.
• B: Equals 50/20, inverting the work formula.
• C: Equals 20 × 25, using half the distance.

Final answer: D