Homework Help: physics

Posted by marr on Sunday, October 9, 2011 at 12:41pm.

an electric motor is used to pull a 125 kg box across a floor using a long cable. the tension in the cable is 350 N amd the box accelerates at 1.2 m/s^2 [forward] for 5 seconds. the cable breaks and the box slows down and stops. calculate the coefficient of kinetic friction?

physics - Henry, Monday, October 10, 2011 at 10:42pm
Wb = mg = 125kg * 9.8N/kg = 1225N. =
Weight of box.

Fb = (1225N,0deg.).
Fp = Fh = 1225sin(0) = 0 = Force parallel to plane = hor. force.
Fv = 1225cos(0) = 1225N = Force perpendicular to plane = The normal.

Fn = ma = 125 * 1.2 = 150N = Net force.
Fn = Fap - Fp - Ff = 150N,
350 - 0 - Ff = 150,
Ff = 350 - 150 = 200N,
Ff = u*Fv = 200,
1225*u = 200,
u = 0.163 = Coefficient of friction.

Fap = Force applied.
physics - Anonymous, Thursday, November 3, 2011 at 9:03pm
a

Answer this Question

Related Questions

Physics - An electric motor is used to pull a 125 kg box across a floor using a ...
Physics - An electric motor is used to pull a 125 kg box across a floor using a ...
Physics - An electric motor is used to pull a 125 kg box across a floor using a ...
Physics - an electric motor is used to pull a 125 kg box across a floor using a ...
Physics - A warehouse employee used a cable to pull a 125 kg crate across the ...
PreAP Physics - A force of 600N is applied to a metal box to pull it 15 m across...
physics - A 14.8 kg box is being dragged 12.5 m across the floor using a rope ...
Physics - A rope is used o pull a metal box 15.0m across the floor. The rope is ...
physics - A large box whose mass is 20 kg rests on a frinctionless floor. A ...
Physics help! - A box of books weighing 323 N is shoved across the floor by a ...

For Further Reading

First Name:
School Subject:
Answer: