Question

Last question bottom

Answer 1

Since the object is sliding at a constant speed, we know that the net force along the direction parallel to the incline must vanish.

Using the notation of the figure, the net force along the direction parallel to the incline is:

`F_R = F_\parallel - F_f.`

Given the geometry of the incline, we have:

`F_\parallel = F_w \sin(19^\circ) = mg\sin(19^\circ).`

Since
`F_R = 0`, we get:

`F_f = F_\parallel = mg\sin(19^\circ) \approx 12 * 10 * 0.33 \textrm{ N} = 39.6\textrm{ N}.`

So the frictional force is:

`\boxed{F_f = 39.6\textrm{ N}}.`