Question

A dog runs down his driveway with an initial speed of 5.00 m/s for 8.00 s, then uniformly increases his speed to 10.0 m/s in 5.00 s.

a. what was his acceleration during the 2nd part of the motion?
b. how long is the driveway?

Answer 1

The acceleration during the second part of the motion is -1.00 m/s², and the length of the driveway is 25.0 meters.

Step-by-step explanation:

a. To find the acceleration during the second part of the motion, we can use the equation:

Acceleration (a) = (Change in velocity)/(Time)

The change in velocity during the second part of the motion is 10.0 m/s - 5.00 m/s = 5.00 m/s. The time for the second part of the motion is 5.00 s. Therefore, the acceleration during the second part of the motion is:

1. Acceleration = (5.00 m/s - 10.0 m/s)/(5.00 s) = -1.00 m/s²

b. To find the length of the driveway, we need to calculate the total distance traveled during the second part of the motion. We can use the equation:

Distance = Initial velocity * Time + (1/2) * Acceleration * Time²

The initial velocity for the second part of the motion is 5.00 m/s and the time is 5.00 s. The acceleration during the second part of the motion is -1.00 m/s². Plugging in these values, we get:

1. Distance = 5.00 m/s * 5.00 s + (1/2) * (-1.00 m/s²) * (5.00 s)² = 25.0 m

Therefore, the length of the driveway is 25.0 meters.