- #1
gruba
- 206
- 1
Homework Statement
What initial velocity has to have a ball at the height [itex]h=1m[/itex] in order to sink in the water to depth of [itex]s=4m[/itex]? How long is the motion of a ball through water? A ball is made of material that has density [itex]\rho=770 kg/m^3[/itex]. Surface tension and friction are negligible.
[itex][/itex]
Homework Equations
Classical mechanics - free fall
The Attempt at a Solution
Ball will fall on water surface after [itex]t_1=\sqrt{\frac{2h}{g}}[/itex].
Time of falling to the bottom of water is [itex]t_2=\sqrt{\frac{2s}{g}}[/itex].
Motion through the water is [itex]t_2-t_1=0,451 s[/itex].
Is this correct?
How to find the initial velocity? Why is the density of a ball [itex]\rho[/itex] given?