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Practice Questions from Module 5: Answer the following theory questions. E-mail your answers to your "homework buddy" and send them feedback on their responses. Remember to cc a copy to me. Once I receive your answers I will e-mail you back with the solutions. 1. A projectile is fired straight upward at 100 m/s. How fast is it moving at the instant it reaches the top of its trajectory? 2. What would the answer to question 1 be if the projectile is fired upward at 45 degrees instead? 3. At what angle should a slingshot be oriented for maximum horizontal range? For maximum altitude? 4. Neglecting air resistance, if you throw a ball straight up with a speed of +20 m/s, what will be its speed when you catch it? 5. Neglecting air resistance, if you throw a baseball at 20 m/s to your friend who is on first base, will the catching speed be greater than, equal to, or less than 20 m/s? What about if air resistance is a factor? Answer the following question. The solution is given below, but make a fair attempt to do the question on your own. If you are having difficulty or do not understand the solution you can either e-mail your "homework buddy" or myself. 1. A golf ball is hit with a velocity of 24.5 m/s at 35.0 degrees above the horizontal. Find a) the range of the ball, and b) the maximum height of the ball. 2. A player kicks a football from ground level at 27.0 m/s at an angle of 30.0 degrees above the horizontal. Find a) its “hang time” (time that the ball is in the air), b) the distance the ball travels before it hits the ground, and c) its maximum height. 3. After retrieving her ball from the roof, a girl throws the ball off of the roof with a speed of 5.6 m/s at an angle of 35 degrees above the horizontal. The ball is thrown from a height of 11 m above the ground. Find a) the time the ball is in the air, b) the range of the ball, c) the maximum height of the ball, and d) the speed of the ball as it strikes the ground.