Answer:
key points:1.momentum and impulse
2.condition for conservation of momentum and why
3.how to solve collision problems
4.centre of mass
Explanation:
momentum is a vector
force of a tennis ball
for a top player,a tennis ball may leave the racket on the with a speed of 55m/s(about 120mi/h).if the ball has a mass of 0.060kg and is in contact with the racket for about 4ms(4×10)s.estimate the average force on the ball
Answer:
If you want, you can make an electromagnet by wrapping wires around a used paper towel roll, but if you want a strong magnet, wrap them around an iron core instead.
Explanation:
sorry if i'm wrong and this does not help please rate this so i can get feedback
Answer:
The work done by gravity moving the box up is -514.5 Joules.
Explanation:
The gravity acts in the direction of the displacement, which in this case is negative (ground - top shelf), and so the resulting work is negative. The work is calculated as:

The work done by gravity moving the box up is -514.5 Joules.
Just like mass, energy, linear momentum, and electric charge, angular momentum is also conserved.
The wheel has angular momentum. I don't remember whether it's
up or down (right-hand or left-hand rule), but it's consistent with
counterclockwise rotation as viewed from above.
When you grab the wheel and stop it from spinning (relative to you),
that angular momentum has to go somewhere.
As I see it, the angular momentum transfers through you as a temporary
axis of rotation, and eventually to the merry-go-round. Finally, all the mass
of (merry-go-round) + (you) + (wheel) is rotating around the big common
axis, counterclockwise as viewed from above, and with the magnitude
that was originally all concentrated in the wheel.
No. Mechanical energy is not conserved. There's quite a bit of friction on the slide. So some of the potential energy is lost to heat on the way down, and the child arrives at the bottom with hot pants and less kinetic energy than you might expect.