My professor insists on lecturing about tension and pulleys all week, then he assigns us problems that have no relation to lecture(adsbygoogle = window.adsbygoogle || []).push({});

I'm having trouble with a few problems, hopefully you can help me.

Grant Hill jumps 1.2 m straight up into the air to slam-dunk a basketball into the net. With what speed did he leave the floor?

This one I'm not sure where to begin. d=1.2 - don't I need time in order to calculate speed?

During a walk on the Moon, an astronaut accidentally drops his camera over a 18.5 m cliff. It leaves his hands with zero speed, and after 2 s it has attained a velocity of 3.6 m/s downward. How far has the camera fallen after 4.1 s?

Interesting. I know that the gravitational constant on the moon is 1.62m/s^2, but I don't know how that comes in to play in regards to calculating the distance. Any ideas?

A 2.0-kg ball tied to a string fixed to the ceiling is pulled to one side by a force (the figure below ). Just before the ball is released and allowed to swing back and forth, (a) how large is the force that is holding the ball in position and (b) what is the tension in the string?

http://img89.imageshack.us/img89/58/fig039ne1.gif [Broken]

I tried T=2(sin30)+2(cos30)= 2.732kg this is apparently wrong.

What do I need to do here?

A marble is rolled so that it is projected horizontally off the top landing of a staircase. The initial speed of the marble is 3.0 m/s. Each step is 0.18 m high and 0.30 m wide. Which step does the marble strike first?

Do I just calculate the horizontal component and divide by the width of the steps?

If you have ANY idea about any of these please let me know. thanks

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# Homework Help: Energy conservation of basketball problem

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