The description of the movement of bodies by their position, velocity, acceleration (and possibly higher time derivatives, such as, jerk) without concern for the underlying dynamics/forces/causes.

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1answer
34 views

Problem with formula for parabolic motus

I know that the path made by an object thrown in air with velocity $v_0$ with an angle $\alpha$ is: $$y=x \cdot\tan \alpha - \frac {gx^2}{2v_0^2\cdot \cos^2 \alpha} $$ At school we had to use this ...
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1answer
31 views

Catapult projectile with different mass [on hold]

We have a physics law. We made catapult and we have to launch a water balloon. However before that we have to know where the water balloon will fall. We don't have radars or stuff like that to ...
-3
votes
1answer
40 views

How to calculate magnitute of average acceleration? [on hold]

Given: Starting from rest the acceleration is 500mph, in 1 second. How do I calculate the magnitude of acceleration for this in terms of $g$ as 9.8m/s^2? Starting off 500mph is about 220 m/s ...
-3
votes
0answers
29 views

How to calcuate uniform circular motion? [on hold]

Given: Ideally, I maintain a speed of 265km/hr and 285 km/hr. Roughly, 73.6 m/s and 79m/s. I make a turn and experience around 4.5g's to 5.5g's, roughly 45 and 55 m/s^2, for about 7 seconds. I ...
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1answer
31 views

How to define the dilatation rate (strain) between two particles knowing the instantaneous positions and velocities?

Provided that I have the instantaneous positions and velocities of two particles that can separate in 3D with respect to time. I would like to characterize the change in length. What could be a good ...
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0answers
13 views

Motion in a straight Line [on hold]

A stone is projected from a height of 300m and at same time another stone is projected vertically upwards with a velocity of 100m/s Find when and where the two stones meet
0
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2answers
30 views

A bullet is fired horizontally from the top of a building, and at the same instant a second bullet [on hold]

A bullet is fired horizontally from the top of a building, and at the same instant a second bullet is dropped from the same height. Ignore air resistance. Which bullet hits the ground first?
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3answers
96 views

Question on acceleration of gravity

In pre-calculus last week my teacher explained a scenario in which a man throws a rock down a well and takes 4 seconds for you to hear the rock hit the bottom. How far downs the well? Last years I ...
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2answers
56 views

What is the percentage of energy recovery in Kinetic Energy Recovery Systems(KERS) in cars?

Kinetic Energy Recovery Systems (KERS) use flywheels to recover energy from the kinetic motion of cars. They use a rotating flywheel that generates energy as it rotates- this generates the electric ...
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0answers
14 views

Angular velocity and linear velocity [on hold]

Define and EXPLAIN average angular velocity and acceleration. Define and EXPLAIN instantaneous angular velocity. Experiment was about throwing a cricket ball. the shoulder is the point of reference. ...
0
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1answer
19 views

Kinematics Word Problem [on hold]

A curling rink is approximately 35 m long from button to button. Mr. Grover releases a rock and 20. seconds later it stops on the far button. What was the initial velocity of the stone? What ...
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4answers
108 views

When does acceleration due to gravity equal positive/negative? [on hold]

For example a projectile is launched at an angle. What would $a$ in $y=vt +.5at^2$ be? Let's say I choose up to be positive. How do you not confuse yourself whether to use positive or negative $a$?
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1answer
110 views

Gas viscosity at high pressure, high temperature

EDIT 1 PER COMMENTS I am wanting to model nitrogen gas viscosity as a function of pressure and temperature OR learn of an existing equation that models nitrogen viscosity for the pressure and ...
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0answers
20 views

Physics Homework help [closed]

If a curve with a radius of 80m is properly banked for a car traveling 62km/h , what must be the coefficient of static friction for a car not to skid when traveling at 92km/h ?
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votes
1answer
17 views

Optics, finding the acceleration of images [closed]

the acceleration of both the blocks of mass m will be g, hence the acceleration of the images will be 2g. acceleration of the two images w.r.t. each other will be 2g + 2g = 4g but the answer is ...
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1answer
46 views

Speed, Velocity and Acceleration

How do you calculate an equation that asks to calculate the final velocity without time being given? But with distance being given...
3
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1answer
52 views

Non-deterministic particle system

This question is in the spirit of Norton's dome, an example of an apparently non-deterministic system in Newtonian mechanics. Under certain restrictions, the Picard–Lindelöf theorem guarantees the ...
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2answers
101 views

Animating an Acceleration Vector - Acceleration of object on a crested path in gravitational field

So I was reading in Chapter 3 of my textbook, Sears & Zemanksky's University Physics with Modern Physics by Young and Freedman, 13th Edition, and the discussion took us to a definition of the ...
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votes
1answer
91 views

How did they solve for $y = -(1/2)gt^2$? [closed]

I am reading through my Physics book lesson and these are the known and unknown values they are discussing. ! So can you please tell me how they went from $y = \frac {-1}{2}gt^2$ to $t = \sqrt ...
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2answers
37 views

Orientation of a rocket going in a circle?

This problem is from my physics homework: A rocket is moving at constant speed in a perfect circle in deep space, far away from any planets or stars. The diagram below shows the circle the ship ...
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2answers
26 views

Finding the point of passing between two objects of different velocities

Let's say an there are two objects or vehicles, both of them travel towards the same direction with constant velocities, the other object being slower than the other. How do you calculate at which ...
5
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5answers
914 views

How does an object's motion behave if dropped from an aeroplane travelling diagonally upwards?

Imagine an aeroplane travelling with velocity $v$ at some angle $\alpha$ from East to North. A box is dropped from the aeroplane. What would the projectile of the box be? Would it be a parabola with ...
1
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1answer
18 views

Instantaneous velocity is slope of displacement-time curve?

I have a toss-up question that I'm not sure how to answer. Here it is (true or false): The instantaneous velocity at a particular time is the slope of the displacement-time curve at that position. ...
0
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1answer
21 views

Confusion about horizonally projected body

DESCRIBED IN IMAGE CLEARLY In the text book, I got the initial velocity of x-component initial velocity Vxi, Vxi = Vi cos(0); (0 = zero) but what if it is like the picture i showed, first it was ...
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2answers
62 views

Converting velocity-time line to acceleration-time?

How would one find where the straight line on a VT graph is on an AT graph? For example in the above image, if I were to convert that into an acceleration-time graph, where on the x-axis would the ...
0
votes
1answer
62 views

Calculating force of a car [closed]

I'm simulating car cruise system and my results are not making any sense. I have been told that my force formula is wrong but I don’t understand why it is wrong and how I can fix this. Does anybody ...
0
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1answer
140 views

Infinite motion on a 3D curve

Suppose we had a curve defined by $$\underline{r}(s) = \alpha \cos(s) \underline{i} + \gamma s \underline{j} + \alpha \sin (s) \underline{k}$$ with $\alpha^2 + \gamma ^2 = 1$ and suppose we had a ...
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1answer
106 views

Correct terminology for combined kinematic and dynamic state

The kinematic state is defined as the position and orientation in space. The dynamic state is defined as the associated velocities. What is the correct terminology for the combined kinematic and ...
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2answers
142 views

Quick question on free fall of 2 objects [closed]

I am trying to work through a problem, that is basically telling me that two objects were dropped from a building, one was thrown 2 seconds after the previous object, and I have to find out how long ...
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3answers
6k views

Stopping Distance (frictionless)

Assuming I have a body travelling in space at a rate of $1000~\text{m/s}$. Let's also assume my maximum deceleration speed is $10~\text{m/s}^2$. How can I calculate the minimum stopping distance of ...
0
votes
2answers
37 views

How do I make an equation to be dimensionally consistent? [closed]

Velocity is related to acceleration and distance by the following expression: $$v^2=2ax^P$$ Find the power P that makes this equation dimensionally consistent. $$\frac{v^2}{2a}=x^P$$ ...
0
votes
1answer
34 views

Frictionless Cart on a Ramp (Experimental Design Question)

Question: Why is the calculated value for our final velocity higher than our predicted value? Since our prediction neglected air resistance and friction, shouldn't the velocity for the actual cart ...
0
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0answers
24 views

How to find the function of acceleration respect to time while having the function of acceleration with respect to velocity [duplicate]

As everyone know that the integral of acceleration respect to time will give the function of velocity respect to time. However, my question concern the different case when the function of a(t) is not ...
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2answers
24 views

What acceleration to use in this problem?

A balloon starts rising from the ground with an acceleration of 1.25 m/second square. After 8 second, a stone is released from the balloon. Find the time for stone to reach ground, distance ...
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1answer
449 views

1D Kinematics - Relative Motion involving non-inertial frames of reference

I recently came across a question involving non-inertial frames of reference. I didn't quite understand the way it had been solved due to some conceptual confusion regarding certain deductions made to ...
0
votes
1answer
48 views

What is the final velocity of a stone dropped out of a rising balloon? [closed]

A balloon is starting from the ground has been ascending vertically at uniform velocity for 4 sec and a stone let to fall from it reaches the ground in 6 sec. Find the velocity with which the stone ...
1
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1answer
147 views

Tangential and radial acceleration in projectile motion

I'm currently learing kinematics, specifically projectile motion and as an example in my textbook is a bullet fired at some angle. I understand the derivation of formulas to describe that motion and ...
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2answers
46 views

Calculate average speed of projectile with air resistance

There's a project that I'm working on that been bugging me for awhile. The project involves this senario: A projectile is released at 1000 feet per second and moves in a straight line infinitely ...
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2answers
86 views

Time of flight for a projectile with stated initial velocity and size at various distances

I've been mooching round the internet looking for an answer to this one and can't find a ready resource, hence the question. In short, I'm trying to discover the flight time of a shotgun pellet at ...
0
votes
1answer
74 views

How do I analyze a system where the magnitude of acceleration is fixed? [closed]

Just to clarify, this is not a homework problem. I'm using this for some code I'm writing for a simulation: I'm trying to find a point at which I should switch from a positive acceleration of a ...
9
votes
4answers
3k views

Can superconducting magnets fly (or repel the earth's core)?

If a superconducting magnet and appropriate power supply had just enough $I\cdot s$ (current $\cdot$ length) so that when it was perpendicular to the earth's magnetic field, the force of the ...
1
vote
1answer
55 views

Circular motion - is average velocity enough to tell?

If I knew the exact value of constant centripetal force and the average velocity of an object travelling around a circle for time $t$, would that be enough information to determine the final positon ...
2
votes
2answers
176 views

Projectile motion maximum distance to origin

Is there an elegant or easy way to derive the maximum distance from the origin to a point of the parabola created by projectile motion (assume initial position is the origin)? Other than ...
6
votes
1answer
220 views

Is it possible to determine particles' velocities from their crossings on a ring?

2 particles are constrained to move in a ring. Both particles begin moving at $t=0$ from $p=0$, each particle moving in the opposite direction of the other. It is known that they are moving at ...
0
votes
2answers
1k views

Can you help me solve a difficult kinematics problem? [closed]

I've been working on this problem for a while now, but I still don't know how to solve it. It involves 2D kinematics, which aren't in themselves hard, but this one threw me for a loop. A ball is ...
2
votes
0answers
27 views

What will be the time taken by a stone to reach the ground if it is thrown with velocity $v$? [closed]

I was studying from my reference book and I got this question. I tried solving it by finding the total distance n average velocity but it didn't work please help me out.
1
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1answer
25 views

How to convert translational energy to rotational energy [closed]

Suppose that I have a body moving at certain velocity in straight line. So it has translational energy. I want to convert this energy to rotational energy of another body, by making the velocity of ...
0
votes
1answer
19 views

Motion and acceleration in a straight line [closed]

A car with an initial velocity of 3 m/s has a velocity of 34 m/s after 3 sec. How far it moves in its third second of motion? acceleration V=U + at a = 10.3 m/s^2 x = ut + 1/2 a t^2 x = 3 (3) ...
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0answers
22 views

Estimate the distance covered [closed]

I know it says estimate, but how? If it's linear I could do something, but it's a curve and so inaccurate. My best try was this. 1000 * 100 = 100000 Which gives me the area of the rectangle which ...
1
vote
0answers
38 views

At time $t=0$, what are the magnitude and direction of the perpendicular component of dp/dt? [closed]

In the dark in outer space, you observe a glowing ball of known mass 4.6 kg moving in the xy plane at constant speed in a circle of radius 7 m, with the center of the circle at the origin (< 0, 0, ...