Answer:
hmax = 1/2 · v²/g
Explanation:
Hi there!
Due to the conservation of energy and since there is no dissipative force (like friction) all the kinetic energy (KE) of the ball has to be converted into gravitational potential energy (PE) when the ball comes to stop.
KE = PE
Where KE is the initial kinetic energy and PE is the final potential energy.
The kinetic energy of the ball is calculated as follows:
KE = 1/2 · m · v²
Where:
m = mass of the ball
v = velocity.
The potential energy is calculated as follows:
PE = m · g · h
Where:
m = mass of the ball.
g = acceleration due to gravity (known value: 9.81 m/s²).
h = height.
At the maximum height, the potential energy is equal to the initial kinetic energy because the energy is conserved, i.e, all the kinetic energy was converted into potential energy (there was no energy dissipation as heat because there was no friction). Then:
PE = KE
m · g · hmax = 1/2 · m · v²
Solving for hmax:
hmax = 1/2 · v² / g
Answer:
1742.24106 revolutions per day
Explanation:
v = Velocity
d = Diameter = 1.1 km
r = Radius = 
g = Acceleration due to gravity = 9.81 m/s²
g = 0.9 g
The centrifugal force will balance the gravitational force


The rotation speed is 1742.24106 revolutions per day
Gravitational force on a satellite is given by the formula

now here we know that force on the satellite is F when its distance from center of Earth is R
Now the distance from the center of earth will be 3R so the force is given as


so if we compare it with initial value of force then it is

so correct answer is

You said T = mg + ma
Subtract mg
from each side: T - mg = ma
Divide each side by m : a = (T-mg) / m
or a = T/m - g
The Net force is 280 N (300-120). The acceleration = force / mass = 280 / 45 = 6.2 m/s^2