How did you find the KE at 0.01m? Hint: Consider the change in potential energy as the position changes, then use that to find the KE.Alt+F4 said:http://online.physics.uiuc.edu/cgi/courses/shell/phys101/spring06/prep2a.pl?practice/exam3/fa02 14. So i just said K = 2, W = 2 M = 2 and found an imaginary Etotal.
then i found the kinetic energy of .01 and when i divide Etot / 4 i get the kinetic energy that my equation gave. What am i doing wrong
Alt+F4 said:http://online.physics.uiuc.edu/cgi/courses/shell/phys101/spring06/prep2a.pl?practice/exam3/sp01 Question 18
what i did was
pgy = .5p v^2
(1000)(9.8)(.03) = .5(1000)(V^2)
V = .77
Ans: .75
So why am i off by .2
Sure the marble takes up room in the cup, but which raises the water level more: having the marble imbedded in the ice, or having the marble tossed in the water? (Hint: Which situation displaces more water?)Alt+F4 said:http://online.physics.uiuc.edu/cgi/courses/shell/phys101/spring06/prep2a.pl?practice/exam3/sp99 19, absolutely makes no sense. The steel marble will take room in the cup right? thus making the intial level higher unless the water overflows but they never stated that
You are only off by 0.02 m/s. Your method looks OK to me.Alt+F4 said:last question. Any hints?
okay so question 18, i understand that it will be the same as inital level, but then 19 there is an object in there that will take room so it will push the water up. I still don't see why the water would be lower? What happened to the water that was at the intial level?Doc Al said:Sure the marble takes up room in the cup, but which raises the water level more: having the marble imbedded in the ice, or having the marble tossed in the water? (Hint: Which situation displaces more water?)
Why is that? What determines the volume of displaced fluid?Alt+F4 said:okay so question 18, i understand that it will be the same as inital level,
It's not just the fact that "it takes room" that's the key. How about this: Imagine a bathtub of water and a big toy boat floating in it. If I take a bowling ball, which will raise the water level in the bathtub more: (1) dropping the ball in the water, or (2) putting the ball on the boat so that the whole thing floats?but then 19 there is an object in there that will take room so it will push the water up.