All Questions
Tagged with relative-motion newtonian-mechanics
200
questions
103
votes
7
answers
112k
views
Why does the atmosphere rotate along with the earth?
I was reading somewhere about a really cheap way of travelling: using balloons to get ourselves away from the surface of the earth. The idea held that because the earth rotates, we should be able to ...
- 7,335
35
votes
5
answers
8k
views
How am I able to stand up and walk down the aisle of a flying passenger jet?
The energy of a moving object is $E = mv^2\;.$ That is it increases with velocity squared.
I walk at say 3 miles per hour, or lets round that down to 1 meter per second for a slow walk. I weigh less ...
- 942
31
votes
7
answers
23k
views
How can kinetic energy be proportional to the square of velocity, when velocity is relative?
Let's start with kinetic energy (from los Wikipedias)
The kinetic energy of an object is the energy which it possesses due to its motion. It is defined as the work needed to accelerate a body of a ...
- 411
21
votes
5
answers
3k
views
Is it possible to stay up while riding a bike on a moving sidewalk without actually moving?
If I ride a bicycle on a moving sidewalk so that I am not in effect moving at all relative to the ground, will I fall over?
- 319
20
votes
6
answers
8k
views
Flying a drone in a moving car/airplane
Why does a drone fly with respect to the air in a moving car/airplane, but not in an elevator as shown in this clip: What Happens If You Fly a Drone In An Elevator?
I understand that the drone will ...
- 415
19
votes
3
answers
7k
views
Why doesn't the speed of Earth (moving through space) kill us?
I have read different speeds of Earth in different sources. $382\;{\rm km}/{\rm s}$, $12\;{\rm m}/{\rm s}$ and even $108,000\;{\rm km}/{\rm h}$. Basically, it's moving too fast around the Sun. And the ...
- 309
15
votes
5
answers
37k
views
A fly in an accelerating car
A fly is flying around in a car, the fly never touches any surface in the car only fly’s around in the air inside the car. The car accelerates. does the fly slam in to the rear window. or does the fly ...
- 151
11
votes
7
answers
5k
views
What happens when the spacecraft velocity equals the velocity at it's exhaust?
So there I was resting me eyes thinking about rocket drives, and what-not. The thought struck me that, perhaps, even before Mr. Einstein interferes with the increasing velocity of the spacecraft Mr. ...
- 4,723
9
votes
3
answers
2k
views
Greatest distance between a particle moving with constant velocity and a particle moving with constant acceleration
Two particles start moving along the same straight line starting at the same moment from the same point in the same direction. The first moves with constant velocity $u$ and the second with constant ...
- 309
8
votes
5
answers
27k
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Speed of a fly inside a car [duplicate]
A couple of weeks ago I was travelling in a car (120 km/h approximately) and I saw a fly flying in front of me (inside the car, near my nose, windows closed). I wonder how was that possible.
Does it ...
- 225
7
votes
6
answers
2k
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Is it wrong to just say that things continue at constant velocity unless acted upon, as velocity is only relative?
Like when saying that people mistakenly thought things automatically slowed down after being thrown etc (accelerated), because that's just due to all the air or surface friction or gravity. Do you ...
user326693
7
votes
3
answers
24k
views
Ball thrown from a moving train
This is not a question about throwing a ball vertically in a moving train. I am asking what would happen if I throw a ball in a horizontally in a moving train. Assume I am facing an exit door of a ...
- 2,479
7
votes
4
answers
3k
views
A Basic Question about Gravity, Inertia or Momentum or something along those lines
Why is it that if I'm sitting on a seat on a bus or train and its moving quite fast, I am able to throw something in the air and easily catch it? Why is it that I haven't moved 'past' the thing during ...
- 329
6
votes
3
answers
516
views
Interesting answer as a range of tension in pulley-block-plane system
I want some intuitive understanding on why there will be a range in tension in the below question. (On solving we will get that the system is at rest ($a=0$) and since its starts from rest the blocks ...
- 95
6
votes
2
answers
680
views
How does the orbital motion of reduced mass tell us how the individual planets/stars move?
To give context to my question, here is Kepler's first Law restated in terms of reduced mass. Here, $\vec{r}$ is the position vector of the reduced mass whose origin lies at the centre of mass of the ...
- 181