Question

At the starting gun, a runner accelerates from rest at 1.8 m/s^2 for 2.2 s. What is the runner's speed 1.0s after she starts running?

Option 1: 1.8 m/s
Option 2: 3.6 m/s
Option 3: 1.0 m/s
Option 4: 2.6 m/s

Answer 1

The runner's speed 1.0 second after beginning is 1.8 m/s, calculated by multiplying the acceleration of 1.8 m/s^2 by 1.0 second, as she started from rest.

Step-by-step explanation:

The question is asking to calculate the speed of a runner 1 second after the starting gun, given that she accelerated from rest at 1.8 m/s2 for 2.2 seconds. Since the acceleration is constant, we can use the formula speed = initial speed + acceleration × time. The initial speed is 0 (since she is starting from rest), and the acceleration is 1.8 m/s2, and the time given in the question is 1.0 second.

Applying the formula: speed = 0 + 1.8 m/s2 × 1.0 s = 1.8 m/s.

Therefore, the runner's speed 1.0 second after starting is 1.8 m/s, which corresponds to Option 1.