2. A child throws a 0.200 kg rock at a tree. When the rock leaves the child's hand, it is moving at 20 m/s and is located 1.5 m above the ground. a. Find the total mechanical energy of the rock.
b. How high above the ground does the rock strike the tree if it is moving at 10 m/s at the instant it hits the tree.

What is the mass of the same rock on the earth

If two students are running down the hall toward each other, trying to get to class, and they have the same mass and acceleration, what will happen when they collide? will their forces cancel out or will each one experience a reaction?

Why is rain likely when warm, moisture-laden air meets cold air? a) the lighter warm air will rise and cool down, causing condensation and rain. b) the cold air moves faster and pushes the warm air away, causing condensation and rain. c) the moisture in the warm air condenses on contact with the cold air, causing rain to fall. d) the cold air mixes with the warm air, reducing its temperature causing moisture to condense.