Answer:
It is impossible to create a perpetual motion machine because some of the energy will always be lost in the conversion and therefore it will eventually stop.
Correct Answer : Option B
Explanation:
The perpetual motion machine is impossible machine as it is hypothetical working machine which would be in motion for an indefinite time in continuity of the motion. The continuity of motion for an indefinite time would mean that the working principle of the machine would never allow the dissipation of energy from the machine and all the machine would ultimately reserve all the energy and be converting it into forms without any loss.
This working principle is violation of first and second laws of thermodynamics and hence a machine will eventually lose some of its energy in every conversion of the working cycle and hence there will be a time where the machine would be stopped, and hence a perpetual motion machine cannot be made.
When three or more coplanar forces are acting at a point and the vector diagram closes, there is no resultant. The forces acting at the point are in equilibrium.
Answer: e. Christian Dopplerâ
Explanation:
Based on the information given, the scientist of the past that should definitely be included in the exhibit is Christian Dopplera.
He described how the frequency of sound waves and light is being affected by the relative speed of both the source and also the observer. This was referred to as the Doppler effect.
In this scenario, the Doppler effect can be used to show how the universe is expanding. Therefore, the correct option is E.
The absence of external force in the outer space, allows the piece of rock to continue moving at the same velocity for thousands of years.
<h3>Absence of external force on the outer space</h3>
The outer space is almost an absolute vacuum, because it's nearly empty. There is no matter such as air in the outer space that will provide an external force needed to change the velocity of the piece of rock.
From Newton's first law of motion, an object in a state of rest or uniform motion in a straight line, will continue in that state unless it is acted upon by an external force.
Thus, the absence of external force in the outer space, allows the piece of rock to continue moving at the same velocity for thousands of years.
Learn more about outer space here: brainly.com/question/24701339
Answer:
C.
Explanation:
If there are the same number of protons (+) as electrons (-) they will cancel out and make the atom neutral.
