Question 19: Laws of Motion

Question

A body weighing 125 kg just slides down a rough inclined plane that rises 1 m in every 2 m . What is the coefficient of friction?

Accepted Answer

Let ÃÂ¸ be the angle of the plane. Since it Ã¢ÂÂrises 1 m in every 2 m of horizontal run,Ã¢ÂÂ
$$	an ÃÂ¸=\frac{1}{2}\,. $$
When the body Ã¢ÂÂjust slidesÃ¢ÂÂ (i.e. zero acceleration),
Ã¢ÂÂ downslope component = frictional force
$$mg\sin ÃÂ¸=\;ÃÂ¼\,mg\cos ÃÂ¸$$
Ã¢ÂÂ
$$ÃÂ¼=	an ÃÂ¸=\frac12=0.50\,. $$
Among the given choices, the one closest to 0.50 is
$$\boxed{\frac\pi6}\;(\approx0.524)\,. $$

Answer

$\frac{\pi}{8}$

Answer

$\frac{\pi}{5}$

Answer

$\frac{\pi}{3}$

Answer

$\frac{\pi}{6}$

Laws of Motion

A body weighing 125 kg just slides down a rough inclined plane that rises 1 m in every 2 m . What is the coefficient of friction?

Choose the correct answer: