Question

A block of mass m is given a kick on frozen pond, imparting an initial speed of $v=4m/s$. Coefficient of friction between block and ice is ${\mu }_K=0.5$. Find the distance the block moves before stopping.

• A. 2.4 m
• B. 0.8 m
• C. 3.2m
• D. 1.6 m

Answer 1

The correct option is D 1.6 m

$W_{friction}=\Delta K.E=0-\frac{1}{2}m{v}^2$
$\frac{1}{2}\text{/}{mv}^2=\mu mgx$, where $x$ is the distance that block moves before stopping.
$x=\frac{v^2}{2mg}=\frac{4\times 4}{2\times 0.5\times 10}=\frac{16}{10}=1.6m$