Question

1. how long does a bicycle whose acceleration is 5 m/s² need to go from 15 m/s to 45 m/s? (a) 6 s (b) 20 s (c) 40 s (d) 400 s (e) none of the above

Explanation:

Step1: Identify the acceleration - time - velocity formula

We use the formula $v = v_0+at$, where $v$ is final velocity, $v_0$ is initial velocity, $a$ is acceleration and $t$ is time. We need to solve for $t$, so we can re - arrange the formula to $t=\frac{v - v_0}{a}$.

Step2: Substitute the given values

Given $v_0 = 15\ m/s$, $v = 45\ m/s$ and $a=5\ m/s^{2}$. Substitute these values into the formula: $t=\frac{45 - 15}{5}$.

Step3: Calculate the value of $t$

First, calculate the numerator: $45−15 = 30$. Then, divide by the denominator: $\frac{30}{5}=6\ s$.

Answer:

(a) 6 s