Thread: Algebraic Vectors & Application

A crate has a mass of 400 kg and is sitting on an inclined plane that makes an angle of 30 degrees with the level ground. Determine the components of the weight of the mass, perpendicular and parallel to the plane. (assume that a 1 kg mass exerts a force of 9.8 N).

My work is below, I have the answer for the weight of the mass parallel to the plane but I am not sure how to get the weight of the mass perpendicular to the plane.

Parallel:

cos 60 = fh/3920
1960=fh
therefore the weight of the mass parallel to the plane is 1960 N. this is correct.

the answer for the perpendicular mass is: 3394.82 N
I can't get this answer. can someone explain to me how?

Originally Posted by skeske1234

A crate has a mass of 400 kg and is sitting on an inclined plane that makes an angle of 30 degrees with the level ground. Determine the components of the weight of the mass, perpendicular and parallel to the plane. (assume that a 1 kg mass exerts a force of 9.8 N).

My work is below, I have the answer for the weight of the mass parallel to the plane but I am not sure how to get the weight of the mass perpendicular to the plane.

Parallel:

cos 60 = fh/3920
1960=fh
therefore the weight of the mass parallel to the plane is 1960 N. this is correct.

the answer for the perpendicular mass is: 3394.82 N
I can't get this answer. can someone explain to me how?

HI

Resolve the weight of mass into 2 components , mg sin 30 and mg cos 30

The one parallel to the plane would be mg sin 30 = (400)(9.8)(sin 30)

THe one perpendicular to plane is mg cos 30 = 400(9.8)(cos 30)

It should be obvious .