The rate of change of velocity of a body per unit of time.
1
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2answers
115 views
If a puck on ice deccelarates, is its speed “v = v0 - t * a” or is it “v = v0 -k * v0”?
I've been wondering about a puck sliding on ice or a puck in an air hockey table game.
If a puck is hit and we start watching it as soon as it has reached its maximum speed and starts becoming slower, ...
1
vote
0answers
183 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 ...
1
vote
2answers
149 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 ...
1
vote
2answers
528 views
Calculating the gravitational acceleration inside of a planet
Plant X has a radius of 5000 km and is composed of two layers.
The first inner layer ranges from the centre to 2000 km from centre, it's density is 8 kg / dm^3.
The second layer ranges from 2000 ...
0
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1answer
100 views
Red shift and time distortion
Superman throws a light emitting object away from himself fast enough to notice a red-shift. The object passes through a region in which time runs more slowly. From Superman's perspective, does the ...
0
votes
1answer
111 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)?
2
votes
1answer
419 views
Force on rope with accelerating mass on pulley
I have a pretty basic pulley problem where I lack the right start.
A child sits on a seat which is held by a rope going to a cable roll (attached to a tree) and back into the kid's hands.
When it ...
0
votes
1answer
200 views
Accelerometer Orientation Conversion
Got two accelerometers that are measuring accelerations oriented at +/- 45 deg from horizontal. I am looking to determine the conversion of the accelerometer measured data to accelerations in the ...
3
votes
2answers
487 views
Classical car collision
I have a very confusing discussion with a friend of mine.
2 cars ($car_a$ and $car_b$) of the same mass $m$ are on a collision course. Both cars travel at $50_\frac{km}{h}$ towards each other.
They ...
0
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0answers
306 views
Two objects with masses Question help [closed]
I got this wrong on a test. Can someone explain how to get the answers? I provided the answers. I just need an explanation.
Two objects with masses of 3.10 kg and 6.90 kg are connected by a light ...
2
votes
3answers
2k views
Convert acceleration as a function of position to acceleration as a function of time?
Suppose I have acceleration defined as a function of position, "a(x)". How to convert it into a function of time "a(t)"? Please give an example for the case a(x)= x/s²
4
votes
5answers
4k views
Distance when acceleration 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 ...
0
votes
0answers
115 views
interstellar travel [closed]
Interstellar Travel
Suppose I'd like to take a trip to a Alpha Centauri, about 25.8 trillion miles northeast of Birdseye, Indiana. Assume I have controlled fusion reactors and access to all resources ...
0
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2answers
3k views
Not sure of a homework solution involving average acceleration
A 50.0 g Super Ball traveling at 25.0 m/s bounces off a brick wall and rebounds at 22.0 m/s. A high-speed camera records this event. If the ball is in contact with the wall for 3.50 ms, what is the ...
-1
votes
2answers
619 views
Formula for getting energy required to accelerate to a certain speed?
I am curious how many newtons it takes to accelerate an object with a given coefficient of drag, reference area, weight, and air pressure? I know this may sound like a simple equation but I have no ...
0
votes
1answer
180 views
calculating of g force in fun ride
we vistited yesterday a fun park and saw a ride which was a big centrifuge only in vertical.
this one had a speed meter but it was broken and i also wanted to know how much g-force is on there...
so ...
0
votes
1answer
108 views
calculating ballast needed to offset wobble of a 1g unbalanced centerfuge spinning at 20000G's
So this seemed pretty straight forward at first, but then I wasnt too sure about gravity forces...
So.
centerfuge
2 samples
1 sample is 1gram heavier than the other
centerfuge at top speed is ...
7
votes
2answers
788 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.
...
9
votes
3answers
429 views
How do we explain accelerated motion in Newtonian physics and in modern physics?
Maybe my question will seem stupid, but I am not a physicist so I have some problems understanding a classic Newtonian experiment: in the bucket experiment, why does he have to introduce the absolute ...
1
vote
2answers
242 views
What method should I use to solve for the final acceleration of a projectile being launched from the earth's surface?
What method should I use to solve for the final acceleration of a projectile being launched from the earth's surface?
The question I am working on is:
A projectile is launched vertically from ...
3
votes
3answers
3k 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 ...
1
vote
3answers
4k 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 ...
3
votes
5answers
557 views
Confused about the role of mass
I'm far from being a physics expert and figured this would be a good place to ask a beginner question that has been confusing me for some time.
According to Galileo, two bodies of different masses, ...
0
votes
2answers
125 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 ...
3
votes
2answers
960 views
Formulas for ball rolling in a bowl?
I'm developing a program where I've a ball/sphere rolling in a bowl from the side at top, till the center at bottom, and I'm trying to get the formulas for:
The rotation angle and the position of ...
0
votes
2answers
2k views
Does an Increase of Force affect the Speed of an object if the acceleration stays constant?
If I had a mass of $100\:\rm{kg}$ accelerating due to gravity, using $F=ma$:
$F = 100\:\rm{kg} \times 9.8\:\rm{m/s^2}$
$F = 980 \:\rm N$...
If I increased the mass to 200kg, the force would be 1960 ...
0
votes
1answer
2k views
How to calculate fuel consumption of car (mpg) from speed and accleration knowing mass, drag coeff and rolling resistance?
How can I calculate the current (instantaneous) mpg of my car if I know the speed and acceleration of the car? From reading various answers for the "car going level or up/down hill" question asked ...
0
votes
3answers
241 views
Deccelerate and Accelerate to achieve timed journey
I have a vehicle traveling at initial speed $100\:\mathrm{m/s}$.
Expected destination speed is also $100\:\mathrm{m/s}$.
Maximum deceleration is $3$.
Maximum acceleration is $10$.
Distance to the ...
8
votes
4answers
312 views
Are smaller soap bubbles more accelerated by wind?
If you blow a bunch of soap bubbles outside, and a gust of wind hits them, will the bigger ones be more or less accelerated by the wind than the smaller ones?
Intuitively, and maybe from remembered ...
6
votes
8answers
697 views
Reactionless Drives
According to the third law of motion, you van't have an mass move in a particular direction unless there is a proportional opposite mass/acceleration ratio in the opposite direction.
No-one has been ...
7
votes
4answers
2k views
Acceleration in special relativity
I am currently studying the motion of relativistic charged particles in electromagnetic fields. More exactly, we first derived the equation of motion in the 4-vector formalism.
I was a bit confused ...
2
votes
2answers
827 views
Gravitational pull vs. acceleration due to gravity
It might seem obvious but i can't imagine how is gravitational pull is different from acceleration due to gravity?
1
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4answers
4k views
Free falling of object with no air resistance
Why does an object with smaller mass hits the ground at same time compared to object with greater mass? I understand the acceleration due to gravity of earth will be same but won't the object with ...
0
votes
2answers
3k views
Stopping Distance (frictionless)
Assuming I have a body travelling in space at a rate of 1000m/sec. Let's also assume my maximum deceleration speed is 10m/sec*sec. How can I calculate the minimum stopping distance of the body?
All ...
42
votes
9answers
7k views
Don't heavier objects actually fall faster because they exert their own gravity?
The common understanding is that, setting air resistance aside, all objects dropped to Earth fall at the same rate. This is often demonstrated through the thought experiment of cutting a large object ...
1
vote
3answers
1k views
How does a lower center of gravity affect fuel economy?
It's been a couple years since I've taken a physics class, and I have been wondering about this basically since I bought my car:
I drive a 2010 Honda Fit, which has a street weight of approximately ...
9
votes
1answer
599 views
How do I calculate the (apparent) gravitational pull with General Relativity?
Assume a static metric with (known) components $g_{\mu\nu}$. I'd like to know what is the gravitational pull $g$ of a test particle placed on an arbitrary point $X$.
The gravitational pull being ...
2
votes
3answers
2k views
Velocity and acceleration question
1.The magnitude of the total force acting on a ball rolling without
slipping down a ramp is greater than
the magnitude of the total force
acting on the same ball if it slides
down the ramp ...
2
votes
1answer
444 views
acceleration of rings in aerotrim (human gyroscope)
I'm working on a graphic simulation (just for fun, for an open-source screensaver) of an Aerotrim - a "human gyroscope", one of those exercise/training machines with a human in the middle, perched on ...
10
votes
7answers
2k views
Would it help if you jump inside a free falling elevator?
Imagine you're trapped inside a free falling elevator. Would you decrease your impact impulse by jumping during the fall? When?
1
vote
1answer
684 views
Finding angular acceleration from torque
We have to analyze this video
Givens:
An applied net torque due to the wind on the windmill is equal to 1500 N*m.
Each (of the 3) propeller props weighs approximately 45 Kg and has a Moment of ...
4
votes
4answers
699 views
Is acceleration an absolute quantity?
I would like to know if acceleration is an absolute quantity, and if so why?
