To determine the average speed of the car, 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 Given Values**: - Distance traveled by the car: \( d = 150 \) meters - Time taken: \( t = 5 \) seconds 2. **Use the Average Speed Formula**: The formula for average speed (\( v_{avg} \)) is: \[ v_{avg} = \frac{d}{t} \] where: - \( d \) is the distance traveled, - \( t \) is the time taken. 3. **Substitute the Values into the Formula**: Plugging in the values we have: \[ v_{avg} = \frac{150 \text{ meters}}{5 \text{ seconds}} \] 4. **Perform the Calculation**: Now, we perform the division: \[ v_{avg} = 30 \text{ m/s} \] 5. **Conclusion**: The average speed of the car during this time interval is \( 30 \text{ m/s} \). ### Correct Option: The correct answer is **B. 30 m/s**. ### Explanation of Other Options: - **A. 25 m/s**: This option is incorrect because it underestimates the average speed. If we calculate \( 150 \div 6 \), we would get 25 m/s, but the time taken is 5 seconds, not 6. - **C. 35 m/s**: This option is also incorrect. It overestimates the average speed. If we were to calculate \( 150 \div 4.2857 \), we would get approximately 35 m/s, but the time taken is 5 seconds, not 4.2857 seconds. - **D. 20 m/s**: This option is incorrect as well. It significantly underestimates the average speed. If we calculate \( 150 \div 7.5 \), we would get 20 m/s, but again, the time taken is 5 seconds, not 7.5 seconds. ### Common Pitfalls: - **Misunderstanding Average Speed**: Some students confuse average speed with instantaneous speed. Average speed is calculated over a time interval, while instantaneous speed is the speed at a specific moment. - **Incorrect Division**: Ensure that you are dividing the total distance by the correct total time. Double-check your calculations to avoid simple arithmetic errors. ### Revision Summary: - Average speed is calculated using the formula \( v_{avg} = \frac{d}{t} \). - For this problem, the average speed is \( 30 \text{ m/s} \). - Always ensure to use the correct values for distance and time. - Be cautious of common mistakes in calculations and understanding the concept of average speed.