A 200 kg boulder is 1000m above the ground. What is the speed of the object right before it hits the ground?

Explanation:

we use the equation for the final speed:

where is the final speed, is the initial speed, is the gravitational acceleration () and is the height.

In this case we don't have an initial velocity indicated so: , and we are told that the boulder is at a height: .

We substitute this values into the equation:

the speed of the object right before it hits the ground is

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.