If you are standing still and a car passes you at 60 mph it appears to be moving at 60 mph
If you are traveling in a car at 60 mph and a car alongside you traveling in the same direction at 60 mph it appears to be not moving, since the relative velocity is 0
Imagine a person riding past in a car who looks at you says to you "I'm not moving. I am sitting still in my car. YOU are moving!"An airline passenger flying overhead then looks down at both of you, and reports "I'm up here sitting still, and BOTH of you guys are moving!".And an astronomer working at the observatory on the moon, taking a break and using his super-duper telescope to see what's shaking back on earth, watches the events on Earth and, and sees clearly that ALL THREE of you are moving.Now here's the important part: all perspectives are correct ! There is no such thing as absolute motion - all mostion is relative to the observer, or the person who is measuring the movement.
All vector quantities, and many scalar ones too, depend on the frame of reference. There is no such thing as "real" speed or "real" direction of motion ... only speed and direction compared to the motion of the person measuring them. Example: A person is sitting in a comfortable seat, with a book in his lap. Since the book is not moving, he's able to read the book, and even drift off and nap for a few minutes. But the person is actually sitting in Row-14, Seat-B of a transcontinental jet flight. A person on the ground who watches the aircraft fly over him sees the book move by at 350 miles per hour ... too fast for him to make out any of the words in it.
Here are some example problems related to Lorentz transformations: A spaceship is traveling at 0.8c relative to Earth. Calculate the time dilation factor experienced by the astronauts on the spaceship. An observer on Earth sees a moving train pass by at 0.6c. Calculate the length contraction factor experienced by the train as observed by the observer. Two spaceships are moving towards each other at 0.9c and 0.6c, respectively. Calculate the relative velocity between the two spaceships as observed by an observer on Earth.
rest and motion are indeed relative terms take for example, you are standing on a platform and see a train speeding past you. the train is definitely in motion with respect to you. now, think of a passenger in the same train..to the passenger the train in at rest but he sees the platform speeding past him, meaning you appear to be in motion with respect to him... this concept is very much relative, as the earth like all the other planets including the sun are actually moving. so though the computer in front of you may seem to be at rest with respect to you, it is actually in motion if someone from the moon or some other planet sees it...:-)
My friend would say that as he passes me, he sees me moving in the opposite direction relative to him. He would also observe a change in the distance between us as he moves ahead of me.
It means the observer is all knowing. For example, people believe that GOD is an omniscient observer, who sees and knows everything
Assuming the Moon is above the horizon, the other observer would also see a first quarter moon.
The planet's progress appears to slow down, or reverse its direction altogether so that it appears to move westward with respect to the stars over a period of many nights. It is important to note that this aberration of motion is an illusion - the planet in question has not changed its orbit in any way. Because of the relative motions among the observed planet and Earth, the observer on Earth sees an illusion, and from the observer's perspective, the planet appears to deviate from its normal orbit.
Imagine a person riding past in a car who looks at you says to you "I'm not moving. I am sitting still in my car. YOU are moving!"An airline passenger flying overhead then looks down at both of you, and reports "I'm up here sitting still, and BOTH of you guys are moving!".And an astronomer working at the observatory on the moon, taking a break and using his super-duper telescope to see what's shaking back on earth, watches the events on Earth and, and sees clearly that ALL THREE of you are moving.Now here's the important part: all perspectives are correct ! There is no such thing as absolute motion - all mostion is relative to the observer, or the person who is measuring the movement.
A nature journal - is simply a list of plants, birds insects and animals an observer sees on a country walk.
Supposing you mean the novel Speak by Laurie Halse Anderson, Melinda compares herself to a rabbit whenever she sees Andy Evans.
An omniscient observer is a hypothetical entity or being that possesses complete knowledge and understanding of all events and information in existence. This concept is often used in philosophy and thought experiments to explore questions of knowledge, perception, and reality.
As long as the observer is some place on the earth, his locationhas essentially no effect on the moon phase that he sees.
That person in London would see a new moon.
We suppose it can, according to two reports from different observers. An observer on the ground sees a passenger jet whizzing by at 400 mph, while a passenger aboard the aircraft at the same time observes it to be sufficiently motionless that she can nap or read a book.
The closest synonym for the word "witness" is "observer" or "spectator," as they all refer to someone who sees something happen.
The retrograde motion of the planets is well modelled by both the Ptolemaic system and the Copernican system, and by the other models. But the Copernican system explains it more simply because, for example, Mars's retrograde motion is caused simply when Mars is overtaken by the Earth, which goes more quickly round the Sun. Thus an observer on the Earth sees Mars appearing to go 'backwards' on the ecliptic around the time of closest approach (opposition). This can be easily demonstrated by assuming simple circular orbits.