Recent content by chamonix

Homework Statement A 12 kg mass is attached to a cord that is wrapped around a wheel with a radius of 10.0 cm. The acceleration of the mass down the frictionless incline of 37 degrees is measured to be 2.0 m/s^2. Assuming the axle of the wheel to be frictionless, determine: a). the force in...

Oh, ok. My fault. Ok. Alpha. so... .5*100*.5^2*.87=10.9=11Nm! ok. Thank you! Sorry, I must have overlooked that alpha part. Thank you.

So...in this case, i should go .5*100*.5^2=12.5? But the answer given is 11 Nm. I don't understand. :(

Homework Statement A potter's wheel of radius 0.50 m and mass 100.0 kg is freely rotating at 50.0 rev/min. The potter can stop the wheel in 6.0 seconds by pressing a wet rag against the rim. a. What is the angular acceleration of the wheel? b. How much torque does the potter apply to the...

Homework Statement A uniform bridge 20 m long and weighing 4.00x10^5N is supported by two pillars located 3 m from each end. If a 1.96x10^4 N car is parked 8 m from one end of the brige, how much force does each pillar exert? Homework Equations (Fgb*L/2+Fgp*d)/L(sin theta). The...

The forces acting on the rider is gravity, normal force which is equal to the centripetal force and the static friction is keeping the persons from falling. So if I use mus=fs/fn and fn=mv^2/r. fs=g g=9.81m/s/s mu=9.81/(5^2/3) mu=.1308 and that's what I got. I think this is correct but am...

Homework Statement In a popular amusement park ride, a cylinder of radius 3.00 m is set in rotation at an angular speed of 5.00 rad/s. The floor then drops away, leaving the riders suspended against the wall in a vertical position. What minimum coefficient of friction between a rider's...

So the mass came out to be...1376.15 kg. Then I used the Fc=mv^2/r equation and got: 1348.63. Then I use the equation Fc=mus*Fn. 1.34x10^3/9.8*1376.15=.0985.

I think so...the question just states "a 13500 N car..." so I was thinking that F=ma so mass=13500/.965=13989.6. But I'm not for sure.

Homework Statement A 13500 N car traveling at 50.0 km/h rounds a curve of radius 2.00x10^2 m. Find the following: a). The centripetal acceleration of the car. b). The force that maintains centripetal acceleration c). the minmum coefficient of static friction between the tires and the road...

Thanks. All the help is greatly appreciated.

So for a. I just use the equation F=ma. then I get F=.025*9.81 and get F=.24525 N and then for b. I use the Fc=mv^2/r and get v=3.13209 m/s Would this be correct?

Oh, ok, so then the two forces (not sure) are the outward force and the gravity, right?

Homework Statement An air puck of mass .025kg is tied to a string and allowed to revolve in a circle of radius 1.0 m on a frictionless horizontal surface. The other end of the string passes through a hole in the center of the surface, and a mass of 1.0 kg is tied to it. The suspended mass...

Oh, I see. So the answer should be positive then.