Answer:
about 19.6° and 73.2°
Explanation:
The equation for ballistic motion in Cartesian coordinates for some launch angle α can be written ...
y = -4.9(x/s·sec(α))² +x·tan(α)
where s is the launch speed in meters per second.
We want y=2.44 for x=50, so this resolves to a quadratic equation in tan(α):
-13.6111·tan(α)² +50·tan(α) -16.0511 = 0
This has solutions ...
tan(α) = 0.355408 or 3.31806
The corresponding angles are ...
α = 19.5656° or 73.2282°
The elevation angle must lie between 19.6° and 73.2° for the ball to score a goal.
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I find it convenient to use a graphing calculator to find solutions for problems of this sort. In the attachment, we have used x as the angle in degrees, and written the function so that x-intercepts are the solutions.
I believe this would be an example of Mary's velocity. We have her speed and direction which is all you need to find velocity.
It would need to be over 20 because if the load of the Pulley E is 20 and the effort is 20, then they will be equal and the Pulley would not move, so your answer is at least 20
Answer:
a person appears at a specified time and place and gives sworn testimony
Explanation:
Hope this helps
Answer:
The change in gravitational potential energy of the climber-Earth system,
Explanation:
Given that,
Mass of the hiker, m = 85 kg
Time, t = 2 h
Vertical elevation of the climber, h = 540 m
We need to find the change in gravitational potential energy of the climber-Earth system. We know that due to change in position of an object, gravitational potential energy occurs. It is given by :
So, the change in gravitational potential energy of the climber-Earth system is 
. Hence, this is the required solution.
