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sand trip with an initial velocity of 45 feet per second. What is the maximum height that the golf ball will reach? Page 2. Solution details for ...
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Let’s solve the example of a quadratic equation involving maximums and minimums for projectile motion
Solution details for problem # To analyze our problems, we will be using a formula for a freely falling body in which we can ignore any effects of air resistance. s(t) represents the projectile's instantaneous height at any time t vo represents initial velocity so represents the initial height from which the projectile is released t represents time in seconds after the projectile is released In this formula, -16 is a constant is based on the gravitational force of the earth and represents ½ g = ½(-32 ft/sec^2 ) = -16 ft/sec^2. Since g , or the acceleration due to gravity, is being measured in ft/sec^2 , we must also measure s(t) , vo , and so in terms of feet and seconds. Let's begin by substituting known values for variables in the formula in problem #1: Since the formula represents a parabola, we must find the vertex of the parabola to find the time it takes for the ball to reach its maximum height as well as the maximum height (called the apex). Using the vertex formula: seconds Substituting into the projectile motion formula we have: feet Therefore, if a ball is thrown directly upward from an initial height of 200 feet with an initial velocity of 96 feet per second, after 3 seconds it will reach a maximum height of 344 feet.
Detailed solution to problem # We will begin by substituting our givens in to the projectile height formula: At time t = 0, v o = 96 ft/sec, and s o = 200 feet. The graph of the equation depicting the path of the ball is as follows: We want to know what the value of t will be when = 300. To find out, we substitute 300 for , and solve the quadratic equation for t. subtract 300 from each side of the equation solve for t using the quadratic formula For a quadratic in the form , the quadratic formula is stated as . We have obtained two values that represent the time that the ball reaches a height of 300 feet. The first value 1. 34 indicates that after 1. 34 seconds have passed, the ball is at a height of 300 feet. Then the ball reaches its maximum height and begins to fall back to the ground. After 4. 66 seconds it is once again at 300 feet. Then it will continue to fall to the ground. The answer we were seeking is 1. 34, the time the ball initially reached 300 feet after it has been thrown.