To determine which object has the greatest acceleration, you would use the formula:
acceleration = (Final Velocity - Initial Velocity) / Time
Just plug-in values for what you have and see which one has the greatest acceleration. If you're given velocity-time graphs, then the one with the steepest slope would have the greatest acceleration.
Answer: 
Explanation:
The equation to calculate the center of mass
of a particle system is:

In this case we can arrange for one dimension, assuming the geometric center of the Earth and the ladder are on a line, and assuming original center of mass located at the Earth's geometric center:

Where:
is the mass of the Earth
is the mass of 1 billion people
is the radius of the Earth
is the distance between the center of the Earth and the position of the people (2 m above the Earth's surface)

This is the displacement of Earth's center of mass from the original center.
Answer:
time is 0.5660 s
and time is - 3.62431 s
Explanation:
velocity u = 15 m/s
height s = 10 m
acceleration due to gravity g = –9.8 m/s²
to find out
time
solution
we will apply here distance equation that is
s = ut - 1/2× gt² ...........1
here put all these value and get time t
here s is height and g is -9.8
so
s = ut - 1/2× gt²
10 = 15t - 1/2× (-9.8)t²
10 = 15t + 4.9t²
solve it we get t
t = 0.56630 and -3.62431
so time is 0.5660 s
and time is - 3.62431 s
Answer:
a)
, b) 
Explanation:
a) The acceleration due to gravity inside the planet is:





b) The acceleration at the surface of the planet is:
