Recent content by cdbowman42

1. The left end of a spring is attached to a wall, When Bob pulls on the right end with a 200N force, he stretches the spring my 20cm. The same spring is then used for a tug-of-war between Bob and Carlos. Each pulls on his end of the spring with a 200N force. How far does Bob's end of the spring...

[b]1.Ball 1 with an initial speed of 14 m/s has a perfectly elastic collision with Ball 2 that is initially at rest. Afterward, the speed of Ball 2 is 21 m/s. What will be the speed of Ball 2 if the mass of Ball 1 is doubled. [b]2. conservation of momentum: m1(v1i)=m1(v1f)+m2(v2f)...

Unless there is a way to get 9.9 N somehow?

Ok well thanks!

Impulse isn't even covered that far into the book, so I don't think that's the way to go. I think we may be missing something.

[b]1. A man sharpens a knife by pushing it against the rim of a grindstone. The 30-cm diameter stone is spinning at 200 rpm and has a mass of 28 kg. The coefficient of kinetic friction between the knife and the stone is 0.20. If the stone loses 10 % of its speed in 10s of grinding, what is the...

Thanks! that's all I needed!

[b]1. A 1.8 kg, 20 cm diameter turntable rotates at 160 rpm on frictionless bearings. Two 500 g blocks fall from above, hit the turntable simultaneously at opposite ends of a diagonal, and stick. What is the turntable's angular velocity, in rpm, just after this event? [b]2. Angular...

Ok that worked. Now, is there an easier way to solve this?

Ok here is my new approach. alpha=angular acceleration r-radius T=Tension M=mass of pulley m1=1.5 kg block m2=2.5 kg block a=acceleration of blocks alpha=Net Torque/I =T1r-T2r/.5Mr^2 =r(T1-T2)/(1/2)Mr^2 alpha =2(T1-T2)/Mr acceleration is in the negative direction...

Ok so the tensions in each side are different. But are the accelerations of both blocks the same?

But assumimg the rope is massless and the pulley is frictionless, wouldn't the tension in the rope be equal to the weight of the blocks?

[b]1. A 2.5 kg block and a 1.5 kg block are attached to opposite ends of a light rope. The rope hangs over a solid frictionless pulley that is 30 cm in diameter and has a mass of .75 kg. When the blocks are released, what is the acceleration of the lighter block. Ok, the book says 2.2m/s^2...

[b]1. A 2.0 kg uniform, horizontal rod is 1 m in length. What is the gravitational torque about the point A that is 25 cm from the left end of the rod. [b]2. T=Fr F=mg T=mgr [b]3. The center of gravity of the rod is directy at its center, so is therefore 25 cm from the...