The particle moves with constant speed in a circular path, so its acceleration vector always points toward the circle's center.
At time
, the acceleration vector has direction
such that

which indicates the particle is situated at a point on the lower left half of the circle, while at time
the acceleration has direction
such that

which indicates the particle lies on the upper left half of the circle.
Notice that
. That is, the measure of the major arc between the particle's positions at
and
is 270 degrees, which means that
is the time it takes for the particle to traverse 3/4 of the circular path, or 3/4 its period.
Recall that

where
is the radius of the circle and
is the period. We have

and the magnitude of the particle's acceleration toward the center of the circle is

So we find that the path has a radius
of

Answer:
Ptolemy proposed a model, he reference system is centered on the Earth
Copernicus, proposed a deferent system, this system is centered on the Sun, where it is at the origin of the system
Explanation:
Thousands of years ago, Ptolemy proposed a model to explain the movement of the planets and stars in the sky, in this model the reference system is centered on the Earth, so each body is orbiting in different spheres around the Earth as its center, this system had very complicated calculations and curves to be able to explain the orbits of the planets.
More recently Copernicus, proposed a deferent system, this system is centered on the Sun, where it is at the origin of the system, in this system the movement of the planets are ellipses, which is a much simpler explanation and has been widely accepted, in current systems the reference system is fixed in the bodies more massive, since this simplifies the explanation of the movements.
Answer:
They sound tinkling in solid hard like metal.
They can vibrate soft surface
I could just Ans this
Answer:
(F)reaction = - 75 N
where, negative sign shows opposite direction.
Explanation:
This question can be answered using Newton's third law of motion. The Newton's Third Law of Motion states that for every action force there is an equal but opposite reaction force.
(F)action = - (F)reaction
Hence, in our scenario if we consider the 75 Newton force applied on the wall to be the action force then the reaction force of the wall must be equal to it in opposite direction. Therefore, the reaction push of the wall must be equal to 75 N.
<u>(F)reaction = - 75 N</u>
<u>where, negative sign shows opposite direction.</u>
Answer: sometimes when people start having an outbreak of it, i guess
Explanation: