Answer:

Explanation:
We know that for circular motion the centripetal acceleration
is:

where v is the speed and r is the radius.
The centripetal acceleration for the astronaut must be the gravitational acceleration due to the gravity, as there are no other force. So
.
The radius of the orbit must be the radius of the Moon, plus the 270 km above the surface




We can obtain the speed as:






And this is the orbital speed.
In an arithmetic progression, consecutive terms differ by the same value.
So, we have

which reflects the fact that the difference between P and 6 must be the same than the one between P and 14.
The equation solves to

And in fact, if you start with

every pair of consecutive terms differ by 4.
Two things can happen to <u>old satellites</u>: For the closer satellites, engineers will use its last bit of fuel to slow it down so it will fall out of orbit and burn up in the atmosphere. Further satellites are instead sent even farther away from Earth.
Answer:
891 excess electrons must be present on each sphere
Explanation:
One Charge = q1 = q
Force = F = 4.57*10^-21 N
Other charge = q2 =q
Distance = r = 20 cm = 0.2 m
permittivity of free space = eo =8.854×10−12 C^2/ (N.m^2)
Using Coulomb's law,
F=[1/4pieo]q1q2/r^2
F = [1/4pieo]q^2 / r^2
q^2 =F [4pieo]r^2
q = r*sq rt F[4pieo]
q=0.2* sq rt[ 4.57 x 10^-21]*[4*3.1416*8.854*10^-12]
q = 1.42614*10^ -16 C
number of electrons = n = q/e=1.42614*10^ -16 /1.6*10^-19
n =891
891 excess electrons must be present on each sphere