So the correct way to go about that is:
mgsin30 - F_f = ma
F_f = - ma + mgsin30
F_f = m (- a + gsin30)
Then plugging in:
F_f = 2 (- 2 + 9.8sin30)
F_f = 5.8
And as it turns out, that is a multiple choice answer, and it is correct.
I'll have the next question up in a bit...
Homework Statement
A 2-kilogram block slides down a 30 degree incline as shown above with an acceleration of 2 meters per second squared. The magnitude of the frictional force along the plane in most nearly:
Then some multiple choice answers.
Homework Equations
F=ma
The Attempt at...
So the three forces are a_c, to the center of the circle, the one that goes tangent to the circle, and perpendicular to a_c, and normal force?
As to the second part of your post... I still don't fully understand...
I'm not sure what you mean by the first question, but with what I think you're saying, centripetal force provides for centripetal acceleration. What I think is probably wrong, though.
For the second question, I'm not sure, but what equation do you want me to apply the method to?
Centripetal Force Question
Homework Statement
The question, straight from the book:
What is the maximum speed with which a 1050-kg car can round a turn of radius 70 m on a flat road if the coefficient of friction between tires and the road is 0.80? Is this result independent of the mass of...