All Questions
Tagged with velocity newtonian-mechanics
467
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Doppler shift from a moving reflector and source if only the relative velocity is known?
Suppose there is a device which is producing and listening to sound (sonar), a reflector is moving with respect to device and the velocity of reflector and device with respect to the air is not known, ...
- 866
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1
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28
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How does the direction of the change in momentum of the object change during the motion?
In the case of an object's movement resembled in this graph, as the gradient is decreasing, a decrease in velocity occurs.
According to the formula
$$p = mv$$,
The momentum is directly proportional to ...
0
votes
1
answer
33
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When does magnetic force affect the velocity of a charged particle
So according to this para, I understand that since one component of velocity is perpendicular to magnetic force (and parallel to magnetic field) that component will not change. But other component is ...
- 91
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2
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Newton's laws on constant velocity [duplicate]
We know that Newton's second law tells us $F=ma+v\frac{dm}{dt}$ so, if a body has a constant velocity but a changing mass, then the equation tells us that the net force acting on the body is $F=v\frac{...
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1
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Friction acting on a moving car
I am trying to understand the nature and direction of friction force acting on from the ground a car driving up an incline.
I was thinking about a simple situation where a car of mass $ m $ is driving ...
- 291
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4
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86
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What is the tangential component of any vector?
There's a statement I discovered in the book I am reading which says
Kinetic energy changes only when speed changes and that happens when the resultant force has a tangential component.
Does that ...
- 91
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2
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89
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What is the science behind why when displacement is increased, so will the final velocity? [closed]
I'm writing a paper and need to write a hypothesis. I did an experiment using a weighted cart with a string and falling mass, and also a pulley. This was completed on a flat table onto the floor. In ...
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1
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42
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Why is velocity proportional to radius in a spherical explosion?
While doing problems on spherically symmetric explosions, I noticed I had been intuitively assuming that velocity scales linearly with radius of the "shell" under consideration. To be more ...
- 135
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This model of friction implies the speed decays exponentially, but shouldn't it actually vanish within a finite amount of time?
A snooker player strikes the cue ball, so that it starts moving with constant speed $v_{0}$. We assume that spin plays no role in its motion. Due to friction between the ball and the cloth of the ...
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3
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How do mass and velocity relate to momentum? [duplicate]
So this is more of a clarifying question. A lot of online definitions state that momentum is a measure of how hard it is to stop or swerve an object, which makes sense. However, the formula for ...
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9
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Where does "excess" energy go when a vehicle uses a lower gear to move at a given speed?
So I understand that a lower gear as advantageous when accelerating a vehicle or when driving up hill (e.g because you are having to accelerate against gravity). I know this is because of the ...
- 191
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2
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Why is velocity used for kinetic energy instead of speed? [duplicate]
This may seem like a self-explanatory question, but if kinetic energy is a scalar quantity, and squaring the velocity essentially removes its vector quality, why not use speed instead?
I have a hunch ...
- 19
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1
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44
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The locus of the velocity vectors of a boat navigating in the sea under the presence of a very strong wind?
I already asked a question very similar to this one here and I think the solution would not work when the boat navigates in the sea when a very strong wind blows. That is I am trying to find the ...
- 159
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1
answer
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In the formula for the conservation of mechanical energy, what does mean the velocity?
For example I have the formula:
MEI=MEF
mgh+mvi2/(2)=mgh+mvf2/(2),
What does initial and final velocity mean?
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3
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In this conservation of momentum problem, where is the sign error coming from?
Say I have a particle travelling in the $x$-direction and breaking into two pieces:
Conservation of momentum in the $x$-direction obviously gives:
$$mv = m_1 v_1 \cos(30) + m_2 v_2 \cos(60).\tag{1}$$
...
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