A person walks 3.0847x10^1 m East, then turns around and walks 8.677x10^0 m West. The total time to walk this distance was 7.8624x10^2 s. What is the speed of the walker, expressed to 3 significant figures?
please help me im so confused
Since the walker turns around and goes backmwards, subtract the second distance from the first. Then divide by the time for the AVERAGE velocity. They asked for average speed, which is something else. It would depend upon how much time was spend travelling at each speed.
They also fail to distinguish between average and instantaneous speed. The question was poorly phrased.
To find the speed of the walker, we need to divide the total distance traveled by the total time taken.
Step 1: Convert the given distances from scientific notation to regular decimal form.
3.0847 × 10^1 m East = 30.847 m East
8.677 × 10^0 m West = 8.677 m West
Step 2: Calculate the total distance traveled.
Total distance = Distance East + Distance West
Total distance = 30.847 m + (-8.677 m) [Note: the West distance is negative]
Total distance = 22.17 m
Step 3: Divide the total distance by the total time to calculate the speed.
Speed = Total distance / Total time
Speed = 22.17 m / (7.8624 × 10^2 s)
Step 4: Convert the speed back to scientific notation.
To express the answer to 3 significant figures, we need to round the speed to three digits after the decimal point.
Speed = 2.819 × 10^-2 m/s
Therefore, the speed of the walker, expressed to 3 significant figures, is 2.819 × 10^-2 m/s.