We know that: sin Ф = cos(π/2 - Ф) ↔ sin Ф = cos(90° - Ф)
Then:
sin 42° = cos(90° - 42°) = cos 48°
IF sin 42° = 2/3, the cos 48° = 2/3
(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:
$20 x 122% = $24.40
or look at it this way:
$20 x 1.22 = $24.40
Step-by-step explanation:
Answer:
20% of $50 is $10. This means that the pair of jeans now cost $60 since it got marked up.
Step-by-step explanation:
The answer is 1 blank, not likely. and 2 blank not used data