Explanation:
The acceleration due to gravity g is defined as
and solving for R, we find that
We need the mass M of the planet first and we can do that by noting that the centripetal acceleration 
experienced by the satellite is equal to the gravitational force 
or
The orbital velocity <em>v</em> is the velocity of the satellite around the planet defined as
where <em>r</em><em> </em>is the radius of the satellite's orbit in meters and <em>T</em> is the period or the time it takes for the satellite to circle the planet in seconds. We can then rewrite Eqn(2) as
Solving for <em>M</em>, we get
Putting this expression back into Eqn(1), we get
I think it’s 25 but I don’t know
Answer: the minimal force that you need to apply to move the bureau is F = 198.45N
Explanation:
If you want to move an object, you need to apply a force that is bigger than the force of the statical friction.
The force of statical friction can be written as.
Ff = k*N
where k is the coefficient of static friction, in this case, k = 0.45, and N is the normal force between the object and the surface.
In this case, the normal force is the weight of the bedroom bureau, this is:
N = m*g = 45kg*9.8m/s^2 = 441N
Then the force is:
Fr = 0.45*441N = 198.45N
This means that the minimal force that you need to apply to move the bureau is F = 198.45N
and after this point, the force of friction will work wit the kinetic coefficient of friction, that usually is smaller than the statical one.
Taking shorter showers, turning off the lights when you aren't in a room, use energy efficient lightbulbs like LED's, use the air conditioning only when you really need it, and use the heat less in the winter.
Answer: 2.67
Explanation: it said he went from 0 to 8 in 3 seconds so if we divide eight By three we get 2.67 rounded to the nearest hundredth so you accelerated that 2.67 m/s
