Recent content by cassie123

Based on the equation for the conservation of energy: if a solid sphere has a smaller moment of inertia it will then have a lower rotational energy than a hollow sphere. So, the solid sphere must have a higher translational energy and reach the bottom at a higher velocity. Better?

Homework Statement Two spheres look identical and have the same mass. However, one is hollow and the other is solid. Describe an experiment to determine which is which. Homework Equations mgh= ½ m v^2 + ½ I ω^2 where I= 2/3 mr2 for a hollow sphere I=2/5 mr2 for a solid sphere The Attempt...

. Nevermind, I gave this way a shot and then the tensions come out as equal. Which wouldn't make sense.

Thanks for your reply! Does this mean that where I used (1.11m-0.2m) as the distance in the torque equation for the sign, I should have just used (1.0m-0.2m)? And Qwertywerty thanks for adding your thoughts as well!

Homework Statement A 30 kg neon sign is suspended by two cables, as shown. Three neighbourhood cats (5.0 kg each) find the sign a comfortable place. Calculate the tension in each cable when the cats are in the positions shown. Ft1 = tension in left cable Ft2 = tension in right cable...

Thanks for your explanation! :)

So it's right as shown? Never mind the other guesses for contact force? Thanks so much!

Homework Statement Three boxes are in contact with each other on a frictionless horizontal surface as shown. The masses of the boxes are m1 = 10 kg, m2 = 20 kg, and m3 = 30 kg. A horizontal force F = 90 N is applied to m1. Calculate: a. the acceleration of the three boxes. b. the net force on...

I gave that shot and ended up with v'1=2.598075 by using the quadratic equation. This makes v'2=1.5 and Θ2=60°. Does that make sense?

Homework Statement [/B] A 2.0 kg ball moving with a speed of 3.0 m/s hits, elastically, an identical stationary ball as shown. If the first ball moves away with angle 30° to the original path, determine: a. the speed of the first ball after the collision. b. the speed and direction of the...

Maybe I'm overcomplicating it. Thanks again!

Thanks SammyS! Yes, that makes more sense that I should subtract. Can I just subtract the south momentum from the east or does the directionality mess that up? Or I think I could also use the change in velocity multiplied by mass. I am getting confused thinking about whether I need to...

Dr. Courtney, thanks for your answer. I'm not sure I understand where to begin following your suggestions

Homework Statement A 15,000 kg loader traveling east at 20 km/h turns south and travels at 25 km/h. Calculate the change in the loader’s a. kinetic energy. b. linear momentum. Homework Equations KE=(1/2)mv^2 p=mv p(i)=p(f) : I am assuming I can ignore gravity The Attempt at a Solution I know...