1. W = F × d = 47 N × 0.26 m = 12.22 J
2. F_net = 47 N - 23 N = 24 N, W = F_net × d = 24 N × 0.25 m = 6 J
3. W = F × d = 2.4 N × 0.75 m = 1.8 J
4. W = F × d, so d = W / F = 2920 J / 62 N = 47 m
5. W = F × d = (20 kg × 9.8 m/s²) × 6.5 m = 196 N × 6.5 m = 1274 J
6. W = F × d, so F = W / d = 520 J / 260 m = 2 N
7. a) W_net = (300 N - 200 N) × 750 m = 100 N × 750 m = 75,000 J
b) W_net = (300 N - 300 N) × 750 m = 0 N × 750 m = 0 J
8. W = F × d, but d = 0 m, so W = 0 J
9. d = v × t = 0.80 m/s × (30 min × 60 s/min) = 0.80 m/s × 1800 s = 1440 m
W = F × d = 40 N × 1440 m = 57,600 J
10. a) h = (10 - 10) × 2.50 m = 0 m, so E_p = 61.2 kg × 9.8 m/s² × 0 m = 0 J
b) h = (10 - 6) × 2.50 m = 10.0 m, so E_p = 61.2 kg × 9.8 m/s² × 10.0 m = 5997.6 J ≈ 6000 J
c) h = (10 - 1) × 2.50 m = 22.5 m, so E_p = 61.2 kg × 9.8 m/s² × 22.5 m = 13494.6 J ≈ 13500 J
11. ΔPE = m × g × h = 10,000 kg × 9.8 m/s² × 10,000 m = 980,000,000 J = 9.8 × 10⁸ J
Parent Tip: Review the logic above to help your child master the concept of work energy and power worksheet answers.
