To determine the power output of the electric motor, we need to follow a series of steps that involve calculating the input power and then using the efficiency to find the output power. Let's break this down step-by-step. ### Step 1: Calculate the Input Power The input power (P_input) of the motor can be calculated using the formula: \[ P_{\text{input}} = V \times I \] where: - \( V \) is the potential difference (voltage) across the motor, - \( I \) is the current flowing through the motor. Given: - \( V = 250 \, \text{V} \) - \( I = 1.5 \, \text{A} \) Now, substituting the values into the formula: \[ P_{\text{input}} = 250 \, \text{V} \times 1.5 \, \text{A} = 375 \, \text{W} \] ### Step 2: Calculate the Output Power The output power (P_output) can be calculated using the efficiency of the motor. The efficiency (η) is given as 80%, which can be expressed as a decimal (0.80). The relationship between input power, output power, and efficiency is given by: \[ \eta = \frac{P_{\text{output}}}{P_{\text{input}}} \] Rearranging this formula to find the output power gives us: \[ P_{\text{output}} = \eta \times P_{\text{input}} \] Substituting the known values: \[ P_{\text{output}} = 0.80 \times 375 \, \text{W} = 300 \, \text{W} \] ### Conclusion Thus, the power output of the motor is **300.0 W**. ### Explanation of Options Now, let's analyze the options provided: - **A. 300.0 W**: This is the correct answer, as we calculated above. - **B. 469.0 W**: This option is incorrect. It does not correspond to any calculation based on the given voltage, current, and efficiency. - **C. 133.0 W**: This option is also incorrect. It is significantly lower than the calculated output power and does not reflect the efficiency of the motor. - **D. 4.8 W**: This option is incorrect and is far too low to be a reasonable output power for an electric motor operating at the given voltage and current. ### Common Pitfalls 1. **Misunderstanding Efficiency**: Remember that efficiency is a ratio of output power to input power. It is crucial to convert the percentage into a decimal when performing calculations. 2. **Forgetting Units**: Always ensure that you are consistent with units (e.g., Watts for power, Amperes for current, Volts for voltage). 3. **Calculation Errors**: Double-check your arithmetic when calculating input power and output power. ### Revision Summary - The input power of the motor is calculated using \( P_{\text{input}} = V \times I \). - The output power is found using the efficiency formula \( P_{\text{output}} = \eta \times P_{\text{input}} \). - The correct output power for the motor is **300.0 W**. - Always convert efficiency from percentage to decimal and ensure unit consistency in calculations.