To determine the average speed of the car during its trip, we can use the formula for average speed, which is defined as the total distance traveled divided by the total time taken. ### Step-by-Step Explanation: 1. **Identify the Total Distance**: The car travels a total distance of 150 kilometers. 2. **Identify the Total Time**: The time taken for this journey is 2 hours. 3. **Use the Average Speed Formula**: The formula for average speed (v) is given by: \[ v = \frac{\text{Total Distance}}{\text{Total Time}} \] 4. **Substitute the Values**: Plugging in the values we have: \[ v = \frac{150 \text{ km}}{2 \text{ h}} \] 5. **Perform the Calculation**: Now, we perform the division: \[ v = 75 \text{ km/h} \] Thus, the average speed of the car during its trip is **75 km/h**. ### Why Option A is Correct: - **Option A (75 km/h)** is the correct answer because it accurately reflects the calculation we performed using the average speed formula. The car covered 150 kilometers in 2 hours, leading to an average speed of 75 km/h. ### Why the Other Options are Incorrect: - **Option B (150 km/h)**: This option suggests that the car traveled 150 kilometers in just 1 hour. However, since the car took 2 hours to cover that distance, this option is incorrect. - **Option C (300 km/h)**: This option implies that the car would have traveled 300 kilometers in 1 hour, which is not possible given the distance of 150 kilometers over 2 hours. Therefore, this option is also incorrect. - **Option D (60 km/h)**: This option suggests a much lower average speed. If the car were traveling at 60 km/h, it would take longer than 2 hours to cover 150 kilometers. Specifically, it would take: \[ \text{Time} = \frac{150 \text{ km}}{60 \text{ km/h}} = 2.5 \text{ hours} \] This is longer than the actual time taken, making this option incorrect. ### Common Pitfalls: - **Misunderstanding Average Speed**: Some students may confuse average speed with instantaneous speed, which can vary during the trip. Average speed is a single value that represents the overall trip. - **Incorrect Unit Conversion**: Ensure that distance and time are in compatible units (kilometers and hours in this case). - **Rounding Errors**: Be careful with calculations; ensure that you perform the division accurately. ### Revision Summary: - Average speed is calculated as total distance divided by total time. - For this problem, the average speed is \( \frac{150 \text{ km}}{2 \text{ h}} = 75 \text{ km/h} \). - The correct answer is **Option A (75 km/h)**. - Other options are incorrect due to miscalculations of distance or time. By understanding these concepts and practicing similar problems, you can improve your skills in calculating average speed and related physics concepts.