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Calculating acceleration function for given time, distance, initial velocity [closed]

An object has an initial velocity of v and should stop in d meters, in t seconds where v*t >= d. I can predict that this acceleration won't be constant but it is a function of time and this problem ...
Mehmet Ataş's user avatar
0 votes
1 answer
176 views

$d=\frac{1}{2}at^2$ not giving expected results

Say I have an object that starts falling from rest at 2 m/s2. Its total displacement and velocity at the end of every second should look something like this: ...
Daniel's user avatar
  • 322
2 votes
0 answers
132 views

Are there bounds or measurements on the derivative of acceleration (jerk)

The title says it all. Is there a physical maximum value to the 3rd derivative of position? Common Lore says that there is not and that jerk does not play any role in physics. My guess is that there ...
lurscher's user avatar
  • 14.7k
2 votes
6 answers
36k views

How can an object with zero acceleration move?

My physics text has a problem in which it is said that a person moves a block of wood in such a way so that the block moves at a constant velocity. The block, therefore, is in dynamic equilibrium and ...
dejay's user avatar
  • 131
1 vote
4 answers
6k views

When we take time derivative of a function of time, then is the result another function of time, again?

(I'll try to explain my question by one known example), for example where the velocity is a function of time v(t) then its time derivative (which is acceleration: $a=\frac {dv}{dt}$) is another ...
vitaly-italy's user avatar
8 votes
3 answers
7k views

Integrating radial free fall in Newtonian gravity [duplicate]

I thought this would be a simple question, but I'm having trouble figuring it out. Not a homework assignment btw. I am a physics student and am just genuinely interested in physics problems involving ...
Kam's user avatar
  • 93
-1 votes
1 answer
1k views

Acceleration, velocity and speed

It is given that acceleration is constant, so can we infer that average speed and velocity are the same?? Moreover, circular motion is out of the question, as the function of x(t) where x=displacement,...
Saurabh Raje's user avatar
  • 1,138
12 votes
3 answers
1k views

Is acceleration an average?

Background I'm new to physics and math. I stopped studying both of them in high-school, and I wish I hadn't. I'm pursuing study in both topics for personal interest. Today, I'm learning about ...
Hal's user avatar
  • 873
3 votes
2 answers
2k views

Utilizing maximum acceleration $a$ for displacement $d$ with initial velocity $v_0$ and final velocity $v_1$

Problem My goal is to move an object from point a to b (displacement $d$) as fast as possible utilizing the maximum available acceleration $a_{max}$, taking into account the initial velocity $v_0$ ...
Jonathan Persson's user avatar
2 votes
1 answer
9k views

Kinematics with non constant acceleration

A particle experiences an acceleration described by $$ a=kx^{-2} $$ where x is the displacement from the origin and k is an arbitrary constant. To what value does the velocity v of the particle ...
Andrew Liu's user avatar
4 votes
2 answers
242 views

Sign of acceleration

I'm developing an application using accelerometer sensor. I'm not good at physics so forgive me if the question is trivial. If I have 3 values of acceleration: $x$, $y$, $z$, I find acceleration ...
Nazerke's user avatar
  • 141
1 vote
4 answers
25k views

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 ...
Saurabh Raje's user avatar
  • 1,138
0 votes
1 answer
739 views

Kinematics question [closed]

An electric train accelerates uniformly from rest to a speed of 20m/s which it maintains until the brakes are applied. It is then brought to rest by a uniform retardation equal in magnitude to twice ...
Taiyaba's user avatar
2 votes
3 answers
4k views

Getting position from an accelerometer on an Android phone

I know that integrating acceleration twice will give me position (acceleration-->velocity-->position) but how can I do all this when I all I have are a set of data points (ex: 1 second = some # m/s^2);...
mathisnotmyforte's user avatar
2 votes
2 answers
6k views

Do you use the magnitude equation to get speed from an accelerometer?

A guy suggested to me that getting speed from an accelerometer required the use of this equation: $\text{speed} = \sqrt{x^2 + y^2 + z^2}$ This does not make any sense to me, all that you would get ...
mathisnotmyforte's user avatar
2 votes
7 answers
44k views

Is acceleration $a = s/t^2$, or $a = 2s/t^2$, or something third?

I'm having trouble understanding some of the stuff regarding movement in my introductory physics class (I never thought I'd say that...) Acceleration is defined as $ a = \frac{s}{t^2}.$ Distance can ...
Daniel Beecham's user avatar
2 votes
2 answers
15k views

Calculate displacement in position from knowing constant acceleration

I have recently started studying physics at school, and my teacher went over the following equation without explaining about it too much: $$s=\upsilon_{0}t+\frac{1}{2}a t^2 $$ I have wondered, why ...
rel-s's user avatar
  • 137
0 votes
2 answers
10k views

How can I add an acceleration vector to a velocity with a different direction?

I am in my last year of high school and am struggling with some homework. I'm sorry if this question is incredibly stupid, but I simply can't find the answer in my notes. If I have an object with a ...
Aeaex's user avatar
  • 1
0 votes
2 answers
1k views

Calculating acceleration increase

...
user1233963's user avatar
15 votes
5 answers
8k views

How to brake 'beautifully'?

Sometimes when I'm driving my car, I play a "game" against myself in which I try to minimize the deceleration felt by passengers (including myself) while still braking in a reasonable short space. I ...
Alpha's user avatar
  • 253
10 votes
6 answers
3k views

Physical intuition for higher order derivatives

Could somebody give me an intuitive physical interpretation of higher order derivatives (from 2 and so on), that is not related to position - velocity - acceleration - jerk - etc?
user680111's user avatar
1 vote
0 answers
59 views

One dimensional motion with changing acceleration. Falling to a large body from a great distance [duplicate]

Possible Duplicate: Radial fall in a Newtonian gravitational field My math and physics are rusty. I am trying to calculate the time an object takes to fall to a large body. Before you answer $1/...
KeithSmith's user avatar
-2 votes
2 answers
1k views

Negative sign of acceleration [closed]

This is the problem from our Physics textbook : A player throws a ball upwards with an initial speed of 29.4 m s–1. (a) Choose the x = 0 m and t = 0 s to be the location and time of the ball at ...
pokrate's user avatar
  • 109
-1 votes
1 answer
15k views

Calculate acceleration and time given initial speed, final speed, and travelling distance? [closed]

A motorcycle is known to accelerate from rest to 190km/h in 402m. Considering the rate of acceleration is constant, how should I go about calculating the acceleration rate and the time it took the ...
pilau's user avatar
  • 117
1 vote
3 answers
34k views

Calculating car's acceleration from change in angle of hanging object? [closed]

The question essentially is based on a situation like this- A car has a small object hung from the cieling on a string (apparently at an angle of 0 degrees to the ceiling). The car is accelerating ...
Sri Kadimisetty's user avatar
0 votes
2 answers
4k views

Center of gravity of vehicle and vehicle performance

I am interested to know how does CG of vehicle plays role in the Fuel economy and the vehicle performance. Does CG of vehicle has anything to do while accelerating of your vehicle. I am a student, ...
Ajay's user avatar
  • 11
1 vote
1 answer
12k views

Calculation of Distance from measured Acceleration vs Time

I have an Accelerometer connected to a device that feeds the instant values of the acceleration in the 3 directions. I've tried to calculate the distance for a vertical movement using these values ...
Francisco's user avatar
1 vote
1 answer
152 views

Vehicle acceleration

What I'm essentially doing is Kalman Filter. If anyone is familiar with (but it doesn't really matter in this case). Consider the following formulas: $$x_k=x_{k-1}+v_{k-1}dt+a_{k-1}\frac{dt^2}{2}$$ $...
c0dehunter's user avatar
10 votes
3 answers
59k views

How can an object's instantaneous speed be zero and it's instantaneous acceleration be nonzero?

I'm studying for my upcoming physics course and ran across this concept - I'd love an explanation.
anjunatl's user avatar
  • 203
1 vote
1 answer
2k views

Suvat equations in reverse direction

This might be a basic question, but please help me out. I have an object traveling in the positive direction with a velocity $v$ and I wish to apply a constant acceleration so that the final velocity ...
Tray65's user avatar
  • 23
0 votes
1 answer
16k views

Finding deceleration and velocity using distance and time

A car is moving down a street with no brakes or gas. The car is slowing due to wind resistance and the effect of friction. The road is flat and straight. The only data I have are timings taken at 100m ...
Jeff's user avatar
  • 3
1 vote
2 answers
2k views

Time and distance where velocity is a function of time

I'm creating a video game set in space in which spaceships travelling between places accelerate until they hit a maximum velocity. They then travel at that velocity until a time when they need to ...
James Coote's user avatar
0 votes
3 answers
1k views

Finding instantaneous speed in MPH given acceleration, RPM and gear ratio

I am still trying to figure out how to (semi) accurately model instantaneous speed after having found acceleration. I have found that at higher RPMs, the resultant acceleration will be lower. I was ...
dtg's user avatar
  • 145
2 votes
1 answer
25k views

Finding acceleration for a car after finding torque

I am trying to calculate the acceleration of a vehicle after finding the torque $\tau$. Assuming my Horse Power is 130 and my RPM is 1000, I calculated torque as: $$\tau = \frac{130 \times 33,000}{2\...
dtg's user avatar
  • 145
3 votes
1 answer
412 views

A practical deceleration question

My friend is a U.S. Army paratrooper. Today, through an unfortunate series of events, he was jerked out of a C-17 traveling at 160 knots by his reserve parachute. First-hand accounts describe it as he ...
Ben's user avatar
  • 33
0 votes
2 answers
3k views

Does acceleration at an angle to velocity change the direction?

During an interval of time, a tennis ball is moved so that the angle between the velocity and the acceleration of the ball is kept at a constant 120º. Which statement is true about the tennis ball ...
Kurt's user avatar
  • 189
0 votes
1 answer
2k views

How to find acceleration given position and velocity? [closed]

Sorry for this very simple question but I am still very new to the laws of motion. I am dealing with 2-dimensional vectors in my programming environment and I'm following these slides to learn about ...
John Tylerc's user avatar
1 vote
2 answers
153 views

Acceleration: Value Disparity?

If we consider a ball moving at an acceleration of $5\ \mathrm{m\ s^{-2}}$, over a time of 4 seconds, the distance covered by the ball in the first second is $5\ \mathrm m$. In the 2nd second will $5\ ...
Ram Sidharth's user avatar
0 votes
2 answers
3k views

Question Concerning Position Of A Particle At Any Given Time

After years of procrastinating i've decided not to "move ahead" with physics without getting this ridiculously trivial question clear!*I know i had asked a similar question as silly and stupid as this ...
alok's user avatar
  • 472
1 vote
2 answers
1k views

Using acceleration to plot position

Sorry if this question is dumb, and I know is physics 101, but I'm not that good with physics. I'm writing an iPhone program that by collecting the acceleration data of the device tries to replicate ...
Nicu Surdu's user avatar
0 votes
2 answers
1k views

How to calculate total distance and time a puck will move?

To simulate a puck's movement, I use the following model (please restrain from discussing the model, it makes the simulation look the way I want it to) and would like to know how to calculate the ...
Krumelur's user avatar
  • 247
2 votes
0 answers
380 views

How to model an accelerometer measurements on a car wheel?

I am working on kinematically modelling an accelerometer on a car wheel. When working on the initial conditions, I am confused whether or not I should use the gravitational acceleration since there ...
Yosef's user avatar
  • 21
1 vote
2 answers
446 views

Is it possible to calculate specific velocities from acceleration?

I'm trying to understand a sample problem from a current (published 2011) high school physics textbook, but I really think the question is flawed. The task is to convert an acceleration-time graph (AT-...
Jack's user avatar
  • 87
0 votes
1 answer
645 views

Find the acceleration based on V² x d graph

How could I find the acceleration of a body knowing only that its position and velocity satisfy $v^2 = f(x)$, where $f(x)$ is a known function of $x$ (position)?
Maxxtack's user avatar
20 votes
5 answers
133k views

How to get distance when acceleration is not constant?

I have a background in calculus but don't really know anything about physics. Forgive me if this is a really basic question. The equation for distance of an accelerating object with constant ...
ben's user avatar
  • 1,527
-1 votes
2 answers
18k views

Not sure of a homework solution involving average acceleration [closed]

A $\rm 50.0 \ g$ Super Ball traveling at $\rm 25.0 \ m/s$ bounces off a brick wall and rebounds at $\rm 22.0 \ m/s$. A high-speed camera records this event. If the ball is in contact with the wall ...
Matt's user avatar
  • 263
7 votes
2 answers
3k views

Should acceleration be included in state vector of a Kalman filter?

I'm developing (actually adopting existing solution) a Kalman filter to model motion of a vehicle (UAV or automobile). The state vector will include position, velocity, and, possibly, acceleration. ...
aimozg's user avatar
  • 73
4 votes
6 answers
11k views

Ion Drive Propulsion Top Speed

I would like to know if there is some formula / graph which would provide / show the efficiency of a certain type of propeller in space. Specifically, I'm interested in the acceleration attainable at ...
Axonn's user avatar
  • 143
1 vote
3 answers
50k views

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

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 ...
user avatar
0 votes
3 answers
10k views

In a 2D problem with a thrown object, why is the acceleration along the x-axis equal to 0?

I'm starting Physics, and I don't understand why the acceleration along the x-axis is zero for an object thrown near the surface of the Earth. This may be problem specific, but I wouldn't know since I ...
Strawberry's user avatar