Final answer:
To find the time when the acorn hits the ground, we set the equation h = 100 - 16t^2 to 0, solve the quadratic equation for t, and find that it takes 2.5 seconds for the acorn to reach the ground.
Step-by-step explanation:
To determine algebraically the time that has elapsed when the acorn hits the ground, you first need to set the equation h = 100 - 16t^2 equal to zero since the height h will be 0 when it hits the ground. Hence:
You then solve for t. Since this is a quadratic equation in the form of at^2 + bt + c = 0, it can be reorganized to:
Divide both sides by 16:
Take the square root of both sides:
The positive value of t is taken since time cannot be negative. Thus, it will take 2.5 seconds for the acorn to hit the ground after it is dropped.