# Question #20d2a

Mar 1, 2016

The diagram below might help

#### Explanation:

We can use the following equation to find the acceleration acting on the sphere along the plane:
$S = u t + \frac{1}{2} a {t}^{2}$
We know u=0, t=5.3s and the sphere travels 1m (distance, s). Hence acceleration = 0.07m/s/s

The force acting along the plane, is the component of the sphere's weight acting along the plan. From the diagram we can see this is $m g \sin \theta$

and since Newton's 2nd law tells us that F=ma we can see that:
$m a = m g \sin \theta$

and the acceleration of the sphere will be given by:
$a = g \sin \theta = 0.07$

We know $\sin \theta$ = 0.01/1
Hence:
$0.07 = g \frac{0.01}{1}$
Hence g, using this, arrives at 7m/s/s. Clearly not 9.8m/s/s! Which suggests friction needs to be accounted for