The rate of change of velocity of a body per unit of time.

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1answer
28 views

Orientation from acceleration?

I have an object that has a sensor attached on it. This sensor calculates the acceleration in all axis and angular acceleration in all axis(Keep the gravity force in mind). How can I get the Pitch, ...
2
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2answers
16 views

Why is the damping force acting on an oscillating system opposite in direction to velocity and not acceleration?

So far I know that the damping force is a frictional force that opposes motion and so it acts in the opposite direction to velocity . Bit why can't the same be said for acceleration doesn't the ...
4
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1answer
88 views

If Speed is Relative can Absolute Acceleration be Real

This is , I suppose not a good question , but I think I am missing something which confuses me in this question. So my question is - Velocity is relative. So suppose a car is moving at a speed 200 ...
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0answers
25 views

Frequency shift due to acceleration of the source towards the receiver [on hold]

How does acceleration of the source towards the receiver change the frequency shift? If a source of sound is accelerating towards the receiver, what should be the graph of frequency due to Doppler ...
-1
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1answer
31 views

What does number of inches per day squared mean?

To give some context to this question, the Pioneer spacecraft were decelerating by: 300 inches per day squared http://www.nasa.gov/topics/solarsystem/features/pioneer_anomaly.html I cannot find ...
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0answers
27 views

A car is moving with constant acceleration at 2 m/s/s. what distance will it have travelled when its velocity is 8m/s [on hold]

a car of length 3m is moving with constant acceleration at 2 m/s/s. How far will its front end be from the start point when its velocity reaches 8m/s The cars back end is on the start point and its ...
2
votes
2answers
115 views

All reference frame are inertial? Where is the flaw in reasoning?

This is my first post here. I have a line of thoughts which might be wrong but I couldn't find the error. Suppose we have a point mass subjected to an arbitrary force $F$. In the lab reference frame ...
0
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1answer
36 views

Acceleration in full-swing pendulum

Consider a $360^{0}$ swing pendulum with a massless rod. If I start it from the position of unstable balance, at the very top of the circumference, according to the conservation of energy, its ...
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0answers
20 views

How can a lateral wind gust create a lateral acceleration for a flying object?

We had a lot of wind today and we weren't able to fly our drone with some friends If a quadrotor of mass $1kg$ flying along the positive $x$-axis at a speed of $4m.s^{-1}$, why would a wind gust ...
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0answers
28 views

Acceleration question- student running after bus [closed]

A student is standing 50 m behind a bus. As soon as the bus begins its motion with acceleration 1 ms-2, the student starts running towards the bus wit a constant velocity u. Assuming the motion to be ...
1
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2answers
49 views

Homework: Angular Acceleration from Net Torque [closed]

I have the correct answer but don't know how that is the correct one. My answers were way off which indicates I am missing something big but don't know what. Now the 4 torques are: t1=6.175, t2=....
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0answers
44 views

A rock dropped onto a car windshield [closed]

The rock is made of concrete and weighs 28 grams. It is approximately 100 mm in diameter. The rock is dropped from an overpass onto a car travelling by at 88 Kph. Would this rock penetrate the ...
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0answers
36 views

rock thrown at a car going 55 mph [closed]

forgive me. I never really studied. My argument is a rock thrown at the windshield of a car moving 55 MPH could easily kill the occupant of said car. Force = Mass X Acceleration. Right?
1
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2answers
78 views

Frame of reference in elevator

I have a conceptual question that I have trouble understanding. An object at the end of a rope is attached to the ceiling of an elevator. If the elevator is allowed to free-fall and hit the ground, ...
-1
votes
3answers
94 views

Why does the period of a pendulum decrease in an accelerating frame? [duplicate]

If there is a simple pendulum in a non-accelerating frame with period $T_1$, it will have period $T_2 < T_1$ when placed in a frame accelerating perpendicularly to the direction of gravity. Why?
2
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1answer
44 views

Collision/Crumpling problem possible solution mistake

This question is from Physics for scientist and engineers , Ohanian . Two automobiles of 540 and 1400 kg collide head-on while moving at 80 kmh in opposite directions. After the collision the ...
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votes
1answer
26 views

Velocity ; Acceleration [closed]

A ball was thrown vertically upwards with a speed of 3m/s. The ball reached a highest point before falling down to the ground. What is the acceleration of the ball at the highest point? A 0m/s2 B ...
0
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4answers
86 views

Explain $\Delta x = v_0t + \tfrac{1}{2}gt^2$ please? [duplicate]

$g = \Delta v/t$, so $\Delta v = gt$. $v = v_0 + \Delta v$, so $v = v_0 + gt$. So if $\Delta x = vt$, then $\Delta x$ should be $v_0t + gt$. Why the $\tfrac{1}{2}gt^2$? I'm really confused, so this ...
0
votes
1answer
30 views

Acceleration at rest when ball is thown [duplicate]

If a ball is thrown vertically upward and it comes to rest for a moment, then its velocity decreases and becomes zero. Does its acceleration also becomes zero? If yes then how ball falls down?
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2answers
39 views

Wheel versus Sphere: Traveling Linearly Down a Track

Assume the following: A tire-like wheel and sphere are both of diameter d and mass m They are both made of the same material They are both resting at the apex of an inclined track An equal amount of ...
1
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4answers
113 views

Why is acceleration of expansion of space unexplained?

I didn't know how to better phrase the question so here we go. It says that the farther we see from our galaxy the faster the other object seems to be going away (accelerating). My common sense ...
0
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4answers
111 views

Is centripetal acceleration constant?

In the case of a car traveling around a corner at a constant speed, the velocity, while constant in magnitude, is obviously changing direction and thus a centripetal acceleration directed towards the ...
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votes
2answers
45 views

How to calculate initial acceleration of a projectile motion? [closed]

I have an object following a projectile motion, that hasn't got horizontal acceleration but only vertical -g. What is the acceleration that I have to use in the second law of motion (F = ma) in order ...
1
vote
2answers
91 views

Relativistic Rocket Fuel Requirements

I am trying to reconcile two different calculations of fuel for a 1g constant acceleration/deceleration trip to Alpha Centauri. One found here (http://math.ucr.edu/home/baez/physics/Relativity/SR/...
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1answer
39 views

Energy required to accelerate from different reference frames

So I've recently been studying relativity a lot trying to understand it and I feel like I grasp most things conceptually but I have one issue I've been trying to understand for the last couple days ...
1
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2answers
53 views

How do I find the linear components of acceleration in a pendulum?

I have managed to derive the equation of motion of a simple pendulum under the influence of gravity using the Lagrangian, but since that only tells me what the angular acceleration is, I now want to ...
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1answer
64 views

Why is angular acceleration of a pendulum always negative?

I was trying to derive using the Lagrangian the equations of motion of a simple pendulum under the influence of gravity. Eventually, I was brought to this conclusion: $$\alpha = -(g\sinθ)/l$$ where $\...
0
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1answer
43 views

If two cars have the same acceleration at time $t$, are the velocities of the cars the same at time $t$?

So when I look at the question logically, I reason that if I had two cars: Range Rover and BMW, at time t, I could pump the gas and make them accelerate at the same rate at 0.5 m/s^2 but I could be ...
3
votes
1answer
76 views

Why didn't I beat the avalanche?

Yesterday, while skiing out of bounds on the south west canyons of Mt. Hood, I experienced a small and extremely mild quake. This, combined with the melting conditions caused an extremely small ...
0
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0answers
40 views

Time of free fall in a repulsive force [duplicate]

The formula for time of a free falling body when acceleration is not constant can be found in any answers here at this site and also at wikipedia. But I haven't been able to find any formula for a ...
0
votes
1answer
34 views

instantaneous velocity center

The instant center of rotation, also called the instantaneous velocity center is the point fixed to a body undergoing planar movement that has zero velocity at a particular instant of time. For ...
0
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2answers
32 views

DC motor acceleration

I'm doing a research project on the mathematics of robotics. For this research project I need to use calculus somewhere in the project. My plan was to calculate the acceleration of the robot and find ...
1
vote
1answer
48 views

Rotational movement at the equator [closed]

What is the centripetal acceleration if you are moving with $100\frac{km}{h}$ on the equator if you are are moving a) east b) west? Shouldn't the acceleration be the same given with $a_{cp}=\frac{v^2}...
2
votes
1answer
30 views

Does an object creates gravitational waves when only accelerating in one direction?

I know from reading about the gravitational waves detected by Ligo, that when an object has angular acceleration, it produces gravitational waves. I'm wondering if an object creates gravitational ...
4
votes
1answer
56 views

Schwarzschild metric, acceleration of ball before it's dropped [duplicate]

The Schwarzschild metric, describing the exterior gravitational field of a planet of mass $M$ and radius $R$, is given by$$ds^2 = -(1 - 2M/r)\,dt^2 + (1 - 2M/r)^{-1}\,dr^2 + r^2(d\theta^2 + \sin^2\...
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1answer
44 views

Time traveled assuming instant acceleration/decelaration

I am working on sort of a motion planning algorithm where I need to estimate the time it takes to travel along a certain path of points (straight lines between consecutive points, i.e I am assuming ...
3
votes
2answers
72 views

Best way of calculating average acceleration in lab experiments

I am doing a lab experiment that works as follows. An object moves along the $x$ axis with an initial acceleration and then moves with a pretty constant velocity that may slightly vary within $20\%$ (...
0
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2answers
76 views

Average acceleration: why I am getting different results?

Let's consider a simple school problem. A car starts moving during 3 seconds with a constant acceleration of 1 m/s^2. Then it stops accelerating and moves 3 seconds more with a constant speed. Find ...
1
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2answers
101 views

I don't understand the formula of constant deceleration required to prevent a vehicle collision

As I was looking for the formula that an Intelligent Speed Assist technology use to calculate the required deceleration that a vehicle must apply avoid collision, I found this one: $$a = \frac{V^2_0 ...
0
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3answers
83 views

Gravitational acceleration of asteroids [closed]

If an asteroid is moving through space at a speed that exceeds escape velocity of the earth and that asteroid is on a collision course with the earth will the asteroid Accelerate as it falls into the ...
0
votes
1answer
27 views

From a displacement-time table/graph, can one tell whether acceleration or jerk is constant?

Does constant acceleration equal a parabolic graph similar to $y=x^2$, while jerk follows the path of $y=x^3$? I was just thinking about this possibility. We are always told in physics class that ...
-3
votes
1answer
65 views

Why does centripetal acceleration equals $v^2/r$?

I have found something on wikipedia, but I don't understand why does the $v(t) \frac{\mathrm du_t}{\mathrm dt}$ equals with $\frac{v^2}{r} u_n$.
0
votes
1answer
135 views

Find constant acceleration needed to reach point (possibly related to projectile motion on slopes) [closed]

Given a particle with a position $p_0$ and an initial velocity $\vec{v_0}$, what acceleration $\vec{a}$ do we need to reach point $p_1$ and how long until we have reached $p_1$? The magnitude of the ...
0
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0answers
12 views

Pulley Advanced Equilibrium Problem [duplicate]

How to show that M would have to be more than 8m
1
vote
0answers
21 views

Position, velocity, acceleration, jolt, and [duplicate]

I am familiar with the fact that $\displaystyle{\frac{dx}{dt}}=v$, $\displaystyle{\frac{dv}{dt} =a}$, and $\displaystyle{\frac{da}{dt}=J}$ where $J$ denotes the 'jolt', or jerk. Are further ...
1
vote
1answer
59 views

Acceleration due to gravity [closed]

Why is it difficult to drink water inside the artificial satellite in the space? I think one of the reasons is that there is no gravity in space and hence we cannot drink water. but I am not sure ...
0
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3answers
69 views

Components of gravity in an inclined plane

The reason the block accelerates down the inclined plane is that the resultant of $N$ and $mg$ acts down the incline. However, why is the force causing the block to accelerate down the incline often ...
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votes
1answer
22 views

Question on weightlessness

An astronaut in an artificial satellite of the earth feels weightlessness. Do they feel weightlessness on the moon too? Why? An astronaut in all artificial satellite feels weightlessness due to the ...