Produces<span> V-shaped valley, steep sides Rapids
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The student that measured the mass to be 16110g got closest to the known result. She is off by 10 g.
The period of a simple pendulum is given by

where
L is the pendulum length
g is the acceleration of gravity
If we move the same pendulum from Earth to the Moon, its length L remains the same, while the acceleration of gravity g changes. So we can write the period of the pendulum on Earth as:

where

is the acceleration of gravity on Earth, while the period of the pendulum on the Moon is

where

is the acceleration of gravity on the Moon.
If we do the ratio of the two periods, we get

but the gravity acceleration on the Moon is 1/6 of the gravity acceleration on Earth, so we can write

and we can rewrite the previous ratio as

so the period of the pendulum on the Moon is
They send out waves differently and cannot be heard easily
Answer: 2.83 minutes
Explanation:
It is understood that trains are approaching. That is, they have speeds of equal magnitude but opposite. When train A travels x meters northbound, then train B travels the same distance southbound.
Therefore trains approach at a speed of:

Then:

Where x is the distance between the trains

So the time in which both trains meet is:

This is:

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<em>How long will it be before they reach one another ?</em>
<h3>2.83 minutes</h3>