Question

sheila weighs 60 kg and is riding a bike. her momentum on the bike is 340 kg·m/s. the bike hits a rock, which stops it completely and throws sheila forward onto the pavement. if there is no net force on the system, what is sheilas velocity immediately after she is thrown from the bike? 1.8 m/s 2.0 m/s 5.0 m/s 5.7 m/s

Explanation:

Step1: Recall momentum formula

Momentum $p = mv$, where $p$ is momentum, $m$ is mass and $v$ is velocity. We need to find $v$, and we know $p = 340\ kg\cdot m/s$ and $m=60\ kg$.

Step2: Rearrange formula for velocity

$v=\frac{p}{m}$.

Step3: Substitute values

$v = \frac{340\ kg\cdot m/s}{60\ kg}\approx5.7\ m/s$.

Answer:

$5.7\ m/s$ (closest option is $5.7\ m/s$ among the given choices although there is a small rounding - off difference in the options presented)