-I somehow ended up with a negative normal force and I know that is wrong becaus

Question

-I somehow ended up with a negative normal force and I know that is wrong because that would mean the ground is pulling on the block.

A 50-lb block has two forces applied on it as shown. The coefficient of friction is 0.2. If the block starts from rest, find the speed of the block after the block has traveled 10 feet. The force is 200(x)cos(x) not 200 times cos(x). -I somehow ended up with a negative normal force and I know that is wrong because that would mean the ground is pulling on the block.

Explanation / Answer

250 + 200*cosx *cos60 - uk *N = ma

250 + 100 *cosx - 0.2 *(mg -200*cosx*sin60) = 50 *a

250 + 100*cosx - 322 + 34.64*cosx = 50a

134.64 *cosx - 72 = 50*a

a = [134.64 *cosx - 72]/50

V^2 = 2*a*10

V = sqrt [ 0.4*(134.64*cosx -72)]

Related Questions

Navigate

• Browse (All)
• Browse #
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.