(a) The maximum height of the ball above the ground is 12.5 m and the time of motion is 1.43 s.
(b) The time taken for the ball to contact the other player at 0.5 m above the ground is 3.0 s.
<h3>Maximum height reached by the ball</h3>
The maximum height reached by the ball is calculated as follows.
At maximum height, the final velocity, v = 0
dh/dt = v = 0
dh/dt = -2(4.9)t + 14
0 = -9.8t + 14
9.8t = 14
t = 1.43 s
H(1.43) = -4.9(1.43)² + 14(1.43) + 2.5
H(1.43) = -10.02 + 20.02 + 2.5
H(1.43) = 12.5 m
<h3>Time to reach maximum height</h3>
12.5 = -4.9t² + 14t + 2.5
4.9t² - 14t + 10 = 0
t = 1.43 s
<h3>Time for the ball to reach 0.5 m above the ground</h3>
0.5 = -4.9t² + 14t + 2.5
4.9t² - 14t + - 2 = 0
t = 3.0 seconds
The complete question is below:
In a volleyball match Hanein serves the volleyball at 14 m/s, from a height of 2.5 m above the court. The height of the ball in flight is estimated using the equation, h = -4.9t² + 14t + 2.5, where t is the time in second and h is height above ground, in metres.
Learn more about time of motion here: brainly.com/question/2364404
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Answer:
Perimeter = 10x + 8 units.
Area = 6x^2 + 13x - 5 units^2.
Step-by-step explanation:
The perimeter is 2*length + 2*breadth
= 2(2x + 5) + 2(3x - 1)
= 4x + 10 + 6x - 2
= 10x + 8 units.
The area = length * breadth
= (2x + 5)(3x - 1)
= 6x^2 - 2x + 15x - 5
= 6x^2 + 13x - 5 units^2.
A cone that is sliced through the vertex would make the shape of a triangle.
You are told the h eight is 10 cm and the radius is 4 cm.
The radius would be half the base, so the base would be 4 * 2 =8 cm.
The area of the triangle is found by multiplying the base by the height, then dividing by two.
Area = 8 x 10 = 80
80 / 2 = 40 square centimeters.
Answer:
60
Step-by-step explanation:
60* of the circumference would be 60-the total circumference.
Answer:
4x-11
Step-by-step explanation:
open parentheses: 4x-8-3
solve: 4x-11