A 250-g ball is thrown into the air with an initial velocity of 22.36 m/s. The kinetic energy, Ek, of the ball is given h(t) = -4.9t2 + 2015 represents the height of the stuntman before he opens the parachute. h(t) = -10.5t + 980 represents the height of the stuntman after he opens the parachute. a) For how many seconds does the stuntman free-fall before he opens his parachute? b) What height above the ground was the stuntman when he opened the parachute? c) Verify your solutions. Did You Know? by the equation E = _5 (d - 20)2 and k 32 its potential energy, E , is given by the _5 p 2 equation Ep = -32(d - 20) + 62.5, where energy is measured in joules (J) and d is the horizontal distance travelled by the ball, in metres.
a) At what distances does the ball have the same amount of kinetic energy as potential energy?
b) How many joules of each type of energy does the ball have at these distances?
c) Verify your solution by graphing.
d) When an object is thrown into the air, the total mechanical energy of the object is the sum of its kinetic energy and its potential energy. On Earth, one of the properties of an object in motion is that the total mechanical energy is a constant. Does the graph of this system show this property? Explain how you could confirm this observation.
Show me your process.
