Answer:
h = 2.5 m
Explanation:
Given that,
Mass of a ball, m = 1.5 kg
Initial velocity of the ball, u = 7 m/s
We need to find the maximum height reached by the ball. Let it is be h. Using the conservation of energy to find it such that,

Put all the values,

So, it will reach to a height of 2.5 m.
This is because Gravity exists everywhere in the universe.
<h3>What is Gravity?</h3>
This is the force of attraction which acts on all matters in the universe. Astronauts appear weightless while in orbiting the Earth because the space shuttle and the astronauts are in free fall around it.
They fall at the same rate as the space shuttle which is why the astronauts appear weightless.
Read more about Gravity here brainly.com/question/88039
Answer:
Take-off velocity = v = 81.39[m/s]
Explanation:
We can calculate the takeoff speed easily, using the following kinematic equation.

where:
a = acceleration = 4[m/s^2]
x = distance = 750[m]
vi = initial velocity = 25 [m/s]
vf = final velocity
![v_{f}=\sqrt{(25)^{2}+(2*4*750) } \\v_{f}=81.39[m/s]](https://tex.z-dn.net/?f=v_%7Bf%7D%3D%5Csqrt%7B%2825%29%5E%7B2%7D%2B%282%2A4%2A750%29%20%7D%20%5C%5Cv_%7Bf%7D%3D81.39%5Bm%2Fs%5D)
Here, we know, according to 3rd Equation of Kinematics,
v² - u² = 2as
Here, u = 0 [ Free fall ]
a = 9.8 m/s² [ constant value for the Earth system ]
s = 15 m
Substitute their values,
v² - 0² = 2 * 9.8 * 15
v² = 294
v = √294
v = 17.15 m/s
In short, Your Answer would be Option D
Hope this helps!