It is true that Gustav Theodor Fechner was the finder of <span>psychophysics. </span>
It lasts 29 1/2 days.
-the sidereal month- is the true period of the moon's revolution around Earth. It lasts 27 1/3 days.
-the difference of 2 days between the synodic and sidereal cycles is due to the Earth- moon system also moving in an orbit around the sun.
Gravitational potential energy, relative to some level =
(mass of the object)
times
(height above the reference level)
times
(acceleration due to gravity) .
The force of friction is 78.4 N
What is force of friction?
Frictional force is the force created when two surfaces come into contact and slide against each other. it is given by the equation:
μ * 
where,
= force of friction
μ = coefficient of friction
= normal force
Given,
μ 
We know,


Subsituing the values in equation:
μ * 

The force of friction is 78.4 N.
To know more about force of friction, check out:
brainly.com/question/24386803
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