Answer:
- The total kinetic energy before accelerating = 750 J
- The total kinetic energy after accelerating = 3,000 J
- Total work done = 2,250 J
Explanation:
Given:
Mass of bicyclist = 50 kg
Mass of bicycle = 10 kg
Initial velocity (u) = 5 m/s
Final velocity (v) = 10 m/s
Find:
(a) What was the total kinetic energy before accelerating = ?
(b) What was the total kinetic energy after accelerating = ?
(c) How much work was done to increase the kinetic energy of the bicyclist = ?
Computation:
Total mass (M) = 50 kg + 10 kg = 60 kg
1. The total kinetic energy before accelerating = 1/2[Mu²]
The total kinetic energy before accelerating = 0.5[(60)(5)²]
The total kinetic energy before accelerating = 750 J
2. The total kinetic energy after accelerating = 1/2[Mv²]
The total kinetic energy after accelerating = 0.5[(60)(10)²]
The total kinetic energy after accelerating = 3,000 J
3. Total work done = Δ K.E
Total work done = 3,000 J - 750 J
Total work done = 2,250 J
