If a ball is batted at an angle of 35 degree, the distance that the ball travels, as a function of the bat speed, is given approximately by D(v)=0.029v^2+0.021v-1
where v is the bat speed in miles per hour and D is distance traveled in feet.
1. Find the distance a batted ball will travel if the ball is batted with a velocity of 90 miles per hour.
2. With what velocity must you hit the ball in order for it to travel at 400 feet.
Difficult Maths question
2009-12-01 5:17 am
回答 (1)
2009-12-01 5:38 am
✔ 最佳答案
1. Distance that the ball will travel= D(90)
= 0.029(90)^2 + 0.021(90) - 1
= 235.79 feet
2. For the ball to travel at 400 feet
D(v) = 400
0.029v^2 + 0.021v - 1 = 400
0.029v^2 + 0.021v - 401 = 0
Solving the quadratic equation,
v = 117.23 or -117.95 (rejected)
So, the velocity should be 117.23 miles per hour.
參考: Physics king
收錄日期: 2021-04-19 20:45:08
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