Two blocks are connected by a rope. Block A = 8kg, Block B = 5kg(adsbygoogle = window.adsbygoogle || []).push({});

Ramp's angle theta is 22 deg. Kinetic friction = .10

The blocks are held motionless, then released. Block A slides up as Block B falls.

Block A is on the ramp connected by a rope to Block B hanging off the side of the ramp and only has the force of gravity down and the tension force up acting upon it.

Can someone please tell me what I am missing/left out of each part and help me set things up right? Thanks

1. Find Net force of Block A parallel to the ramp

Uk = coeff of kinetic friction

mass A * accel A = -mg sin theta + Uk mg cos theta

mass A * accel A = 8* -9.8 * sin 22 + .1 * 8 * 9.8 * cos 22

2. Find Net force of Block B vertically

mass B * accel B = -mg + Ftension

mass B * accel B = -5 * 9.8 + Ftension

3. You should have two equations with three unknowns: tension in the string, accel_A, and accel_B. The magnitude of the two accelerations should be equal. Figure out if they have the same sign, or opposite signs.

You should now have two equations for two unknowns, the tension in the string and the acceleration of the boxes. Solve for the magnitude of this acceleration.

Check your work: if all is well, then you should be able to solve for the tension in the string using the box A equation. You should also be able to solve for the tension in the string using the box B equation. It should turn out to be the same tension

I am stuck here, I don't know how to combine them and get them the way it wants. Also, Since I should be able to solve for tension in the Box A equation, I must be missing something in the Box A equation.

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# Homework Help: Friction and Force problem! Help!

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