1. **Stating the problem:** A machine applies an effort of 20 N to lift a load of 120 N. The effort moves through 50 m, and the load moves through 200 m. We need to calculate: (I) The efficiency of the machine. (II) The velocity ratio. 2. **Formulas and important rules:** - Efficiency ($\eta$) is given by the ratio of the work output to the work input, expressed as a percentage: $$\eta = \frac{\text{Load} \times \text{Load distance}}{\text{Effort} \times \text{Effort distance}} \times 100$$ - Velocity ratio (VR) is the ratio of the distance moved by the effort to the distance moved by the load: $$\text{VR} = \frac{\text{Effort distance}}{\text{Load distance}}$$ 3. **Calculate the efficiency:** - Work output = Load $\times$ Load distance = $120 \times 200 = 24000$ J - Work input = Effort $\times$ Effort distance = $20 \times 50 = 1000$ J - Efficiency: $$\eta = \frac{24000}{1000} \times 100 = 2400\%$$ 4. **Calculate the velocity ratio:** $$\text{VR} = \frac{50}{200} = 0.25$$ 5. **Interpretation:** - The efficiency is unusually high (2400%), which suggests an error in the problem statement or units because efficiency cannot exceed 100%. - The velocity ratio is 0.25, meaning the effort moves a quarter of the distance the load moves. **Final answers:** - Efficiency = 2400% - Velocity ratio = 0.25