The time rate of change of the position of an object

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Terminal Velocity

Let Suppose a bullet of 2 gram is falling with the speed of 200km/h. Now how can we know the time after which it gains it terminal velocity. Also when it gain its terminal velocity the force of ...
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83 views

Can a bullet leave a gun and tumble to the ground?

This question seems to have been asked a few times in different configurations, but none of them answer my variation. I've struggled to understand this for nearly 15 years and had conflicting answers ...
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1answer
89 views

determining orbit parameters (eccentricity, length and angle of major axis)

I'm trying to make an orbit simulator, and I want to draw the orbit of a satellite given its position and velocity vectors in a 2-D plane. I found this other question which tells how to calculate ...
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2answers
91 views

Gravity mitigated by velocity regardless of mass?

We know that a small object moving fast enough can pass by a planet and escape its gravity. Would this be (theoretically) true in reverse? Meaning a planet moving fast enough past a stationary smaller ...
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2answers
1k views

Difference between deltaV and specific impulse

When reading any literature regarding space propulsion, I keep getting about these terms deltaV and ISP or specific impulse. I know specific impulse is supposed to be the velocity the propellant mass ...
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1answer
3k views

Find velocity and displacement from force equation

How to find velocity and displacement equations from a given force equation? For instance, it was given the following 1-D equation: $$F = b_1(v_1-v) - b_2 v$$ $v_1$, $b_1$ and $b_2$ are constants. ...
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3answers
252 views

How long does it take for an electric car to go from 0 to 60 mph?

I found the freefall motion equation which describes terminal velocity of a falling body, but I can't find a similar equation for a vehicle subject to constant traction force, so I tried determining ...
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1answer
93 views

Determine orbital position after change in velocity

I am working on a satellite simulator for a project/game and I am stuck on this one bit of physics. So far I have a satellite that revolves around earth on a 2D plane following Keplerian motion using ...
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1answer
318 views

Newtons Cradle, Collision Theory

It has come to the point in my computing program now where I have 5 swinging pendulums that are all modified at once by slider values. These values are drawn onto the from and passed through the class ...
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1answer
146 views

Do these equations apply to an object on a zip line or slope?

I was looking at the conversion equations for Potential Energy to Kinetic Energy to Velocity here: http://www.ftexploring.com/energy/PE-to-KE.html Would these apply to an object on a zip-line? ...
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264 views

Functions of Time

1) Is position a function of time only or also velocity? Likewise, is velocity a function of time only or also the position? 2) The following are functions of time: $s(t)$ = distance a particle ...
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Deriving equations of motion using integration

Please refer to my school textbook pg48 (of the book, and not the pdf counter) here: http://ncertbooks.prashanthellina.com/class_11.Physics.PhysicsPartI/ch-3.pdf My doubt is in this context: (right ...
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2answers
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What does the velocity of a wave mean?

I know that the velocity of a wave is given by $v=\lambda f$ but what does this velocity represent in the physical sense. For instance, if I am told a car moves at a velocity of 5 $m/s$ I know that ...
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1answer
734 views

Calculating velocities using Reference frames

Suppose an object A is traveling at a velocity of 100 m/s, and another object B is traveling at 105 m/s. With both the objects traveling through the same direction, taking A as a reference frame, the ...
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2answers
189 views

Trains travelling at different speeds towards a station C

Here's the question: Consider two stations A and B located 100 kilometer apart. There is a station C, located between A and B. Now trains from station A and B start moving towards station C at ...
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2answers
649 views

At what point does a projectile leave a slingshot?

Assuming a frictionless / "perfect" environment, and given a ball held in an elastic sling (like a hand-held catapult) where the pocket is lighter than the projectile itself, what is the point at ...
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2answers
777 views

Sign of Velocity for a Falling Object

I'm working on a homework problem in Mathematica. We have to graph the height and the velocity of a function given an initial height and initial velocity. However, when I do the graph for the velocity ...
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3answers
429 views

Numerical simulation of mechanics problem

Say I have a planet and shoot something with a given velocity, which is a significant portion of the escape velocity, in a given angle into the sky. It has some initial velocity and there is the force ...
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3answers
7k views

Find radius of curvature, given a velocity vector and acceleration magnitude?

The particle P moves along a space curve. At one instant it has velocity $v = (4i-2j-k)$ $m/s$. The magnitude of the acceleration is 8 $m/s^2$. The angle between the acceleration and the velocity ...
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1answer
153 views

Is it theoretically possible for the orientation angle of a projectile to remain exactly equal to the orientation of velocity?

This question is sparked by my answer to this question: Is this simulation following real physics? After examining the math, I don't see how it is theoretically possible for the situation simulated ...
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1answer
21 views

Spinning theoretical object moving faster than the speed of light [duplicate]

Let's say you have the Earth, or any celestial body, spinning as it is. What if you build a tower from the surface, and extended it out into space. If it was built far enough, could the furthest end ...
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1answer
55 views

Calculating the energy of an electron given the wavelength

Okay, so I know that the wavelength of an electron is 5e-7m and I am asked to calculate its minimum velocity and hence minimum energy. Calculating the minimum ...
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2answers
38 views

Final position of an object after aplying several horizontal forces [closed]

I'm given an object with a starting position. Several horizontal forces are applied to this object one after the other for different amounts of time. How can I determine the final position $x$?
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1answer
31 views

Velocity in the lift equation

What exactly is the nature of the velocity in the lift equation? I have read that it is the velocity of the aircraft, and I think I have read that it is the relative velocity of the air to the ...
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1answer
240 views

Using the Maxwell-Boltzmann distribution function to find specific molecule speeds?

I've been looking for problems to practice on this topic and found a problem asking to use the Maxwell-Boltzmann distribution function to calculate the fraction of Argon gas molecules with a speed of ...
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2answers
282 views

I don't understand the idea of perpendicular vectors being independent of each other?

So problem 71-75 is about vectors. The problem says: A river has a current flowing with a velocity of 2.0 meters per second due east. A boat is 75 meters from the north riverbank. It travels at ...
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1answer
117 views

Angular Momentum of Two Non-interacting Particles

I'm reading a book (An Introduction to Mechanics by Kleppner) where they calculate the angular momentum $l$ of a system of two non-interacting particles, but I don't understant what are they doing. ...
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1answer
85 views

Why pulse waves results in wave packets?

I was doing experiments of measuring sonic velocity and I generate pulse waves from sensor 1, but when they are received by sensor 2, I saw wave packets on the oscilloscope, can you explain why? I was ...
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2answers
2k views

Calculating Average Velocity

I understand that the concept of an average of a data list means finding a certain value 'x', which ensures that the sum of the deviations of the numbers on the left of 'x' and on the right of 'x' ...
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2answers
166 views

Escape Velocity question

I would like some help in understanding the derivation of the formula for escape velocity. Why does $t$ approach infinity? And why is $v(t)$ approaching zero? I know that $r(t)$ is infinite because ...
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1answer
328 views

Velocity of real gas molecules?

It is known that the velocity of ideal gas molecules can be computed using Maxwell-Boltzmann law of distribution of molecular velocities, with average velocity given as: ...
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1answer
244 views

How much runway does the space shuttle need to land?

A textbook question proposes the following scenario: NASA needs to plan emergency landing sites for the Space Shuttle (RIP). There are a number of things to consider. The shuttle touches down no ...
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3answers
831 views

when an object moves downward, is its height negative?

the question is: A ball is thrown directly downward with an initial speed of 8.00m/s from a height of 30.0m. After what time interval does it strike the ground. so i went through the problem and ...
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1answer
156 views

Determining Orbital Velocity

Is there any way to determine the orbital velocity of a point around another stationary point, if I don't know the mass of either of the points but know the force that gravity exerts and the distance ...
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1answer
6k views

How to find maximum velocity

I stack a question about projectile question. The question was A projectile is being launched from ground level with no air resistance. You want to avoid having it enter a temperature inversion ...
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244 views

Horizontal Speed of Descending Parachute

I understand how to get the vertical (descent speed) of a parachute and its payload, but how could one find the horizontal speed/velocity of this parachute depending on the speed of the wind? (yeah I ...
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1answer
239 views

Measuring a Rod in Motion with two Synchronized Clocks

An explanation of special relativity I'm struggling with, goes like this: A rod traveling by a "stationary" observer has its length measured by use of two stationary synchronized clocks (synchronized ...
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1answer
756 views

Sound velocity in water

Conductivity, temperature, depth sensors are used by oceanography to calculate the velocity of sound at varying depths. These measurment values are used to comprise sound velocity profiles like the ...
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1answer
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Velocity measurement in relativistic perpsectives

I understand the precepts of relativistic time dilation, but I'm looking to nail down the local perception of velocity in each frame. this has three parts, with the second being the most complex ...
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281 views

Find initial velocity when given max height of 100m [closed]

A ball is thrown straight up. The height of the ball above the ground in (m) is given by the function: $$h(t)=-5t^2 + vt + c$$ What is the initial velocity if you want the ball to reach a max height ...
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0answers
21 views

How far will the first spacecraft travel before the second one catches up to it? [closed]

A spacecraft leaves the point of origin and has a maximum acceleration of 30 m/s. It can only maintain this rate for 10 minutes before it runs out of gas and then proceeds to drift at a constant ...
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70 views

How to formally write down the Boltzmann equation?

Can someone write down the Boltzmann equation, not neglecting any of the variables of the involved functions and integrals? Specifically, how to concisely capture the "primed" variables in a sensible ...
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52 views

What do the components of light velocity look like in polar coordinates?

The Schwarzschild solution makes use of polar coordinates, and I'm wondering how the different components of velocity of light change with the position. Might I get some examples of light velocity ...
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55 views

Two impulses on body

Say I have a physics simulation with a single body with three degrees of freedom (two axis and rotation). I have two impulses of equal magnitude in opposite directions. When applying these impulses in ...
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0answers
74 views

Is there any place you can safely skydive without a parachute?

While trying to explain to someone how a kitten walked away from a fall from a skyscraper I got to wondering if there's any place a human could do that and I find myself out of my depth. The only ...
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4answers
16k views

Finding the force of friction of a moving object and its change when it accelerates to a constant speed

I have been searching for a straight forward answer to this question for ages now and it is driving me crazy. Here is what I know: If an object is moving at a constant speed the force of friction ...
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0answers
103 views

A 0.1kg ball of dough is thrown up with a velocity of 15m/s. What is the momentum halfway up? [closed]

I know that $p=mv$ and (0.1kg)(15m/s)=1.5 kg m/s and the momentum at the vertex is 0, but what is the momentum halfway up?
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70 views

Truck driven from a small motor that can carry a heavy load, yet can travel fast.

I am building a truck from trash as materials. I have one small motor and a a few small gears, but no other engineered materials are allowed. The truck must carry a load for a distance of 3m. The ...
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1answer
304 views

Projectile motion problem with upward acceleration and horizontal velocity [closed]

An electron in a cathode-ray tube is traveling horizontally at 2.10×10^9 cm/s when deflection plates give it an upward acceleration of 5.30×10^17 cm/s^2 . B.) What is its vertical displacement during ...
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What direction a flag on an object moving in the wind shows?

"The flag of a ship that is moving northward with 10 km/h, points exactly southwestward. The windsock at the lighthouse points under 30 relative to the western direction southward. Calculate the ...