Answer to Question #274387 in Physics for Dhea

Question

A 45kg block ar rest was pushed by a 280N horizontal force up a 30degree inclined plane with a roughness coefficient of 0.15, what is the netforce acting on the block

Answer 1

1) Determine the normal force:

$$N=mg\cos\theta+F\sin\theta.$$

2) Find the force of friction:

$$f=\mu N=\mu(mg\cos\theta+F\sin\theta).$$

3) The net force:

$$F_\text{net}=F\cos\theta-f,\\\space\\ F_\text{net}=F\cos\theta-\mu(mg\cos\theta+F\sin\theta)=164\text{ N}.$$