An SUV weighing 5800 pounds is parked on a street which has an incline of 10 degrees. Find the force required to keep the SUV from rolling down the hill and the force of the SUV perpendicular to the hill.

Question

mathmate · Answer

Resolve the weight of the vehicle (mg) into the normal to and along the inclined plane.  These two components are the ones required by the question.
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anonymous · Answer

So, it would be \[5800\sin \Theta  5800\cos\ Theta]?

mathmate · Answer

Yes, that is correct, except...
g is acceleration due to gravity, and equals 32.2 ft/s^2.
The mass (5800 lbs) must be multiplied by g to get the weight (mg) in poundals, which is in force units.
If you skip g (which you could), you have to express the unit as lb.force.
For example,
10 lb mass will create a weight of 322 poundals, or 10 lb.force. (or 10 lb. weight)

anonymous · Answer

How did you find the acceleration due to gravity?

mathmate · Answer

This is a constant that is usually given or understood.
In the metric system, it is 9.8 m/s^2.  In the imperial system, it is 32.2 ft/s^2.
However, it depends on the unit you use locally, it could be poundals (mg) or simply lb.force or lb.weight (m).  Lb by itself is a mass.  Gravity exerts a force on the mass to give a weight.  Hope you have studied the difference between mass and weight.

anonymous · Answer

Ah, okay. Thank you.

mathmate · Answer

You're welcome!   :)