All Questions
44
questions
-1
votes
1
answer
98
views
Speed is equal to distance divided by time but is this correct?
In this study https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9784821/, the distance the punch travelled from start to impact is 0.49 meters and the time taken from start of punch (that's it, they define ...
- 364
11
votes
1
answer
866
views
Northern lights / aurora borealis "pre-warning" - how does this work w.r.t timing and different particle / wave speeds?
There is an article in the newspaper today entitled "Northern lights predicted in US and UK on Monday night in wake of solar storms".
I assume that the reason that someone can make this ...
- 213
0
votes
3
answers
217
views
Why is it that objects inside a moving train tend to move at the same speed as the train itself?
I mean I get people saying because it's Newtonian mechanics. Everything inside the train will have same speed as that of train but my question is why ? Why is it like that ? And How does that happen ?
...
- 294
0
votes
0
answers
36
views
Product of two 4 positions without writing the components
I was able to solve the first part of the following question by expanding the terms as vectors
I can't understand how to do it without expanding so I had a look at the answers.
I understand how we ...
- 13
-5
votes
1
answer
74
views
Reality of speed and time [closed]
I have a very simple question. How does a faster object takes less time for the same distance? A car with a speed of 100km per hour takes one hour to travel 100km while a car with the speed of 50km ...
0
votes
2
answers
135
views
When will the 2 cars Have equal speeds? [closed]
If car1 started at 20m, with initial velocity of -4m/s and acceleration of 3 m/s^2.
Car 2 started at 15m, with initial velocity of 6m/s and acceleration of 0. At what time will the 2 cars have equal ...
- 103
3
votes
1
answer
235
views
Why does it take $2d/\lvert v_1 - v_2\rvert$ time to overtake? (Can physics catch-up to math?)
The following answer is from this post.
So it becomes particularly easy to see that the opposite-direction meetings must occur at the interval $2d/(v_1 + v_2)$ and that the overtaking meetings must ...
- 177
2
votes
0
answers
71
views
Number of meetings of $2$ cars starting from opposite ends of a road [closed]
Question:
$2$ cars travelling at $108,75$ kmph respectively, start from the opposite ends of a $90$ km straight road. Travelling back and forth continuously for $10$ hours, how many times do the $2$ ...
- 177
-1
votes
2
answers
110
views
Is the speed of objects in time, in Galilean Relativity, a constant and invariant speed relative to all reference frames?
(This question is only about Galilean Relativity. Not Special or General relativity.)
Question: Is it true that every object in the universe, according only to Galilean Relativity is traveling in time ...
- 107
0
votes
1
answer
554
views
How does Air Resistance affect the motion of a plane?
I am learning basics of physics, I have a doubt regarding air resistance.
Plane 1 and Plane 2 have same mass and surface area.
If plane 1 starts its flight by applying 500N force (numbers are rough ...
- 3
3
votes
3
answers
449
views
Confusion regarding the derivation of pressure in Kinetic Theory of Gases
I was studying the derivation of the relation between pressure ($P$) and root mean square speed ($v_{\text {RMS}}$) of an ideal gas from Fundamentals of Physics by Halliday, Resnick, Walker. (The same ...
user249968
-2
votes
2
answers
87
views
Is there an optimal intergalactical travelling speed? [closed]
In our perceiveable world, an increment of speed typically results in needing less time to travel a given distance. When I go by car, it takes less time then going by bike. However, there is the ...
- 101
2
votes
2
answers
119
views
Measuring the solar system's speed through ether with the help of an eclipse
In A.P. French's Special Relativity, the author said,
Jupiter has
a period of $12$ terrestrial years, and so in half a terrestrial year,
while the earth moves from $A$ to $B$ (Fig. $2$-$7$), ...
- 1,292
1
vote
3
answers
94
views
Find velocity from acceleration equation [closed]
Suppose the acceleration of a particle is a function of $x$, where
$$a(x) = (2.2 s^{-2})x$$
(a) If the velocity is zero when x = 1.0 m, what is the speed when x = 3.4 m?
(b) How long does it take ...
- 13
0
votes
1
answer
46
views
Would not the oscillation of light slow down the wave? [duplicate]
Would not the oscillation of the light wave slow down the wave? Does light travel at "c" of its net position over time, or does it travel at "c" on the wave?
