The strength of the gravitational field is given by:

where
G is the gravitational constant
M is the Earth's mass
r is the distance measured from the centre of the planet.
In our problem, we are located at 300 km above the surface. Since the Earth radius is R=6370 km, the distance from the Earth's center is:

And now we can use the previous equation to calculate the field strength at that altitude:

And we can see this value is a bit less than the gravitational strength at the surface, which is

.
The same amount of work being done over a long period of time!
Answer:
Continental drift describes one of the earliest ways geologists thought continents moved over time. Today, the theory of continental drift has been replaced by the science of plate tectonics.
The theory of continental drift is most associated with the scientist Alfred Wegener. In the early 20th century, Wegener published a paper explaining his theory that the continental landmasses were “drifting” across the Earth, sometimes plowing through oceans and into each other. He called this movement continental drift.
Answer:
z
Explanation:
x repersents a new moon and the others repersent quarter moons
(x is a new moon because new moons are often the phase when the moon is close to earths sun)
Answer:
ε = 2 V/cm
Explanation:
To calculate the mobility inside this bar, we just need to apply the expression that let us determine the mobility. This expression is the following:
ε = ΔV / L
Where:
ε: Hole mobility inside the bar
ΔV: voltage applied in the bar
L: Length of the bar
We already have the voltage and the length so replacing in the above expression we have:
ε = 2 V / 1 cm
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ε = 2 V/cm</h2><h2>
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The data of the speed can be used for further calculations, but in this part its not necessary.
Hope this helps