Question

Before hanging new William Morris wallpaper in her bedroom, Brenda sanded the walls lightly to smooth out some irregularities on the surface. The sanding block weighs 1.70 N and Brenda pushes on it with a force of 3.00 N at an angle of 30.0° with respect to the vertical, and angled toward the wall. What is the coefficient of kinetic friction between the wall and the block?

Answer 1

Answer:

1.0193

Explanation:

The concepts that we apply here is Frictional Force with a Force on the object with a angle.

We know that Frictional Force is equal to

$F_f = \mu N$

The force acts downward because the moving is upward, then from the image that I attached, the forve is equal to,

$Fcos30° = 3N(cos30) = 2.6$

In Y we have then

$1.7N + f_x = 2.6$

$f_x = 1.529N$

For the horizontal componentes we have that

$N = (3N)sin30\°$

$N = 1.5 N$

Using the first equation we have that

$F_f = \mu N$

$1.529N = \mu 1.5 N$

Re-arrange for $\mu$

$\mu = 1.0193$