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.
The upward force of the chain on the diamond would be the tension in the chain, and this tension would have to support the weight of the 45g that hangs from the chain.
mass = 45 g = 45/1000 kg = 0.045kg
Weight = mg = 0.045 * 10 ≈ 0.45N, g ≈ 10 m/s²
<span>So the upward force is ≈ </span><span>0.45N. </span>
work is distance * force so 15*100=1500
and to find time you know power = diastance * force / time
so 25=15*100/t
25=1500/t
25/1500=t
.016=time
Answer:
Distance travelled is 7 meters and the displacement is 3 meters
103.9 hours, if you never stopped for any reason.
