All Questions
Tagged with relative-motion newtonian-mechanics
200
questions
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3
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What exactly will happen if you jump in the upward direction from a roof of on a moving car?
I'm not a physicist and I'm a little bit puzzled with the image below:
I know it's a joke but if we assume we don't have air resistance what exactly will happen if someone jump in the upward ...
- 13
0
votes
2
answers
88
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Question about relative motion from "A Brief History of Time" [closed]
I read this example in Stephen Hawking's A Brief History of Time:
If one sets aside for a moment the rotation of the Earth and its orbit round the Sun, one could say that the Earth was at rest and ...
- 1
2
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2
answers
129
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Confusion regarding Inelastic Collisions contradicting my book
Suppose two bodies $A$ and $B$ with equal mass are kept at a distance. $A$ starts moving towards $B$ at a constant velocity, they hit, and I assume that it is a PERFECTLY INELASTIC collision here.
...
- 1,168
4
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3
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Kinetic energy "paradox" -- where am I wrong here? [duplicate]
Body $A$ is at rest and has mass $2$, so the energy required in order to accelerate it to a speed of $v$ is $v^2$, and so the energy required in order to accelerate it to a speed of $2$ is $4$.
On the ...
- 143
2
votes
5
answers
123
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If motion relative to a frame of reference is purely relative, how do we account for the work done to move relative to the frame of reference?
I get the idea that everything is in motion, and there's no absolute reference frame for everything.
But when we consider local events, like a train passing through a town, I have trouble accepting ...
9
votes
3
answers
2k
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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
2
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0
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55
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Should the velocity increase or decrease?
Suppose some projectile is traveling along the positive $x$ direction at a velocity $v$. While moving it is emitting particles, and thus losing mass. If the particles are being emitted in the same ...
- 1,791
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76
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Doubt regarding derivation of rocket equation
I'm having quite some issues deriving the ideal rocket equation, and I suspect it is due to lack of identifying scalar terms and vector terms. Here is how I derive it :
Let $v$ be the velocity of the ...
- 1,791
6
votes
3
answers
516
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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
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557
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Calculating the velocity of a tennis ball after impacting a moving racket
Suppose I have a tennis ball moving with $v_1$ (blue arrow in first image below) impacting a moving tennis racket with velocity $v_r$ (black arrow in first image below)
In order to calculate the ...
- 103
1
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2
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Power Demand for Motion of Vehicle on a Road and Plain in Air with Air Resistance
Let's say we have an ideal motorcycle without frictional losses (no tire slip, ideal machine without losses). But we want to consider wind force which is proportional to the square of speed
$F = k \...
- 1,299
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0
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114
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Work done on a moving cart in wind
Let us suppose a cart is moving in a rough ground with a propeller attached to the roof of the cart.
Let the velocity of the cart at the given point of analysis be V and velocity of wind is -W. The ...
3
votes
2
answers
279
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Can we use relative motion if acceleration of two bodies are different?
Suppose, on the $x$-axis, a body $A$ is moving with velocity $v_1$ and acceleration $a_1$, and a second body $B$ is moving with velocity $v_2$ and acceleration $a_2$. $B$ is at a distance of $S$ from $...
3
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2
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67
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Relative Velocity (Kinematics) [closed]
I was studying the concept of relative velocity and after solving a few problems I am running into this confusion.
a) Let’s say two cars are moving perpendicular to each other (no collision) with ...
- 31
2
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3
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I am moving right and rain is falling vertically down.Why should I hold umbrella at an angle?
This is related to relative velocity.I get that, from my moving frame of reference rain is making an angle.But still... it doesn't make sense to hold umbrella at an angle when rain is falling ...
