Vertical Motion Problems: Can You Solve These?

[nerdgirl14]

I am having trouble solving these vertical motion problems, please attempt to solve these and explain/show solution so that I can follow

1.A helicopter, which is rising vertically at 20 m/s is 25 m from the ground when an object is dropped from it. How high will the object rise after it is released? For how long will it rise? What will be its speed as it reaches the ground?


2. A stone is dropped from a point 320 meters above the ground; at the same instant another stone is thrown upward from a point 100 meters below the first. I f the two stones strike the ground simultaneously, what is the initial velocity of the second stone.

3. An object is projected vertically upward from the ground. If its initial speed had been twice as great it would have risen 60 m higher. What was the speed of the projection of the object?

 

[ashishsinghal]

use Newtons laws of motion ... nothing complicated.
hint:
when the object is dropped it has same velocity as the helicopter

 

[gneill]

I am having trouble solving these vertical motion problems, please attempt to solve these and explain/show solution so that I can follow

Sorry, doesn't work that way here. You've got to show your own attempt at solution first, or at least a solid description of what you have tried or what approach you think is needed. Then we can offer advice. Nothin' personal; It's the Physics Forum rules.