Question

A skier approaches the base of an icy hill with a speed of 12.5 m/s. The hill slopes upward at 24° above the horizontal. Ignoring all friction forces, what is the acceleration of this skier when she is going up the hill?
A)9.0 m/s2, directed down the slope
B)4.0m/s2, directed down the slope
C)4.0m/s2, directed up the slope
D)9.0 m/s2, directed up the slope

Answer 1

when object is placed on inclined plane then we will have net force along the inclined plane which is due to the component of weight along the incline

so we can say that

$F_x = W sin\theta$

$F_x = mgsin24$

now in order to find the acceleration we can use Newton's II law

$F_{net} = ma$

$mgsin24 = ma$

$a = g sin24$

$a = 4 m/s^2$

and the direction is along the inclined plane downwards as weight always pull downwards

So correct answer will be

B)4.0m/s2, directed down the slope