Object moving through space due to the exertion of a force.

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1answer
27 views

Air resistance and computing the maximum height

How do we compute the height of a ball when the velocity with which it was thrown up and the velocity with which it returned to my hand is given. The velocity with which it was thrown and with which ...
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1answer
44 views

Velocity-time-distance problem

In my book the formula for the $y$-component of velocity during the upward projectile motion is given: $$V_y=V_{iy}-gt$$ and next to it the formula for $y$-component of velocity during the downward ...
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0answers
27 views

What affects the motion of a projectile? [closed]

I love physics, and I am recently getting started to know a lot about physics. I won't deny though that I am pretty knew on the subjects, so things such as drag, and external ballistics are foreign to ...
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4answers
108 views

Force required to send ball in set trajectory

If I have a desired 2D trajectory where I know the desired speed of my ball and desired path, and a ball that starts at (x=0,y=0), how can I calculate the required force / point at which the force ...
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3answers
91 views

Reach @ jumping from one building to another

Let's assume I'm in the rooftop of a building (Building A) and want to jump to the rooftop of another building (Building B). Forget about injuries... is just hypothetical. Building A has a height of ...
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0answers
12 views

The effect of relative wind on a falling body with an initial velocity

I'm working on a physics simulation that calculates the flight path of a projectile fired perpendicularly from a moving aircraft. Once the bullet leaves the aircraft, the program iterates over small ...
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3answers
417 views

Explanation of Supplee's paradox

I was reading about Supplee's paradox, which is about whether a relativistic projectile, subject to uniform gravitational acceleration, would float or sink underwater. However the solution of the ...
1
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1answer
39 views

Find the height and the velocity of the object [closed]

A bolt is detached from the lower part of an elevator cabin that is ascending with velocity 6meters/second and for 3 seconds comes to the point from where the elevator started to ascend. Find: in ...
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2answers
48 views

Rocket altitude [duplicate]

I have a model rocket I'm planning to launch. I heard from someone that you can calculate the altitude by timing the rocket from the time it takes off to the time it lands. Does anyone know how to do ...
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0answers
48 views

Are these two equations correct? [closed]

I know this is a pretty simple question, but like there should be room for those as well. I have the following two formulas describing how long it'll take for an object to decelerate. For example if ...
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1answer
42 views

Formula - Bounce height with respect to time

I'm trying to graph a bounce with respect to time. I have these formulas: $\frac 12 mV_2^2 = mgH_2$ and $H_2 = \frac{1}{2} \frac{V_2^2}{g}$ I will have a series of $H(t)$ formulas as I know how to ...
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0answers
49 views

Motion of projectiles

I was reading Feynman's lectures about the law of gravitation and came across this experiment: Assuming vacuum, if the ball that was shot horizontally was shot so that it would land at a location ...
4
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1answer
479 views

How does a hollow-point bullet move smoothly through the air, presenting a 'cup-shaped' nose instead of an actual sharp-point to the fluid?

Hollow-point rounds move smoothly through the air when presenting a 'hollow cup-shape' instead of a traditional 'sharp point' to the fluid air. Does this mean the air trapped, and at some assumed ...
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0answers
37 views

How does the ball move? [closed]

A lift is moving up with a constant velocity. The passenger in the lift throws a balls horizontally with constant velocity. How will the ball appear to move for a person standing outside the elevator. ...
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2answers
177 views

Terminal Velocity of 100lb Hail [closed]

In the Apocalypse there is meant to be hail weighing 100 pounds or 45 kg. What would the terminal velocity be, assuming the hailstones are perfect spheres of solid ice? Also, is there a way to guess ...
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2answers
40 views

Phsyics Energy Problem + Concept

A simple problem really. Part 1 Suppose a ball ($20. ~kg$) was shot straight up with an initial velocity of $+50~m/s$. a. Assuming that all of the ball's initial $E_k$ was transformed into ...
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7answers
3k views

What does an undefined formula in physics mean?

I am trying to figure out how undefined formulas in mathematics relates to physics. Take the following formula for terminal velocity. $$V_\text{terminal} = \sqrt{ mg \over{c \rho A}} $$ Say we have ...
5
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2answers
691 views

What was the muzzle velocity of a homemade gun launched straight up if air time was 8.2sec?

I built a potato gun and wanted to calculate the muzzle velocity. I remember from physics that I could run the numbers by calculating time from launch until landing. After pointing straight into the ...
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1answer
33 views

Phase space orbit for a projectile [closed]

After playing around with drawing the phase space orbit for a harmonic oscillator I started wondering about the case for a free falling object. So the equations of motion are: $$ P = P_0 + mgt $$ ...
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1answer
70 views

2D Kinematics and Projectile Motion [closed]

In this page, I have finished most of the problems. Some of them I am unable to figure out. For 3 a-j, is it possible to solve this problem given parts a and b, that is, can I solve these problems ...
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1answer
101 views

Trajectory of a projectile in a three dimensional space [closed]

$g$: the gravitational acceleration—usually taken to be $9.81\:\mathrm{m/s^2}$ near the Earth's surface $θ$: the angle at which the projectile is launched $v$: the speed at which the projectile is ...
1
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0answers
44 views

The angle of a rifle to hit a target (How to make approximations to find numerical answers) [closed]

The specific question is this: A target appears at a distance of 1250m with the centre of the target 1.2m above ground level. If the sniper was firing from the prone position, the tip of the ...
2
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1answer
95 views

How far will the bullet travel before falling back to earth? [closed]

First, the question: A particular high performance rifle cartridge can be fired with a muzzle velocity of 1200 meters per second. The rifle is pointed straight up. Assuming there is no air ...
0
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1answer
78 views

Solve for launch angle in projectile motion equation

I need help solving the projectile motion equation for $\theta$. The projectile motion equation is $$ y = \tan(\theta)x - \frac{gx^2}{2v_0^2\cos^2(\theta)}. $$ How do we solve it so that $\theta$ ...
2
votes
1answer
1k views

Dropping a ball in a fast moving train

If I drop a ball in a train moving at a constant speed, will it land on the spot I aimed it at or a little away as the train has moved while it was in air? If it lands away, will the observer not know ...
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0answers
32 views

Clarify throwing an object [closed]

Say I were to throw a 1 kg ball vertically upwards 100 m/s, with g=10 and also air resistance $0.01v^2$. By considering the forces I can determine that the speed at which it lands is less than the ...
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votes
1answer
238 views

Rocket projectile motion problem [closed]

I'm not really sure where to start with this question: In a brisk wind from the south-east of $14.1\:\mathrm{m/s}$ a rocket pointed due north is launched from a cliff that is $500\:\mathrm{m}$ above ...
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2answers
275 views

How to find the height at which a projectile is launched from an angle? [closed]

I need guidance with the following question: A boat is $50.0m$ from the base of a cliff, fleeing at $5.00m/s$. A gun mounted on the edge of the cliff fires a shell at $40.0m/s$ and hits the boat ...
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2answers
4k views

Vertical motion initial velocity given max height

I'm having a hard time finding a formula that calculates the initial vertical velocity for a projectile that should reach a certain height. I'm using this formula to calculate both vertical and ...
1
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1answer
91 views

Whether a large or a small ball fall faster in the air?

Given a ball falling under gravity is subjected to air resistance, after performing a differential to the drag equation, I get: $$g-Z(v^2)/r = a = v',$$ (where $Z$ is a constant.) How can I know ...
1
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1answer
849 views

Time of a ball going up and down with air resistance

A ball is shot directly upward, and then it comes back to the place where it was shot. Suppose we have air resistance. Suppose $t_1$ is the time period from the moment that the ball was shot to the ...
0
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2answers
58 views

Why time of flight remains same for a projectile even though collision takes place?

Why time of flight remains same for a projectile even though collision takes place ? Suppose a ball is projected with some velocity V with some angle θ the the time of flight is T. Now if another ...
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4answers
321 views

Conservation of momentum in a baseball

Conservation of momentum: A thought experiment. A baseball is placed on top of a baseball holder, the kind used to train young batters. A batter hits the stationary ball perfectly horizontal, sending ...
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6answers
771 views

What is the acceleration at the top most point of a ball’s journey vertically upward?

When i shoot a ball vertically upward, it’s velocity is decreasing. So there is acceleration. -9.8m/s^2. I’ve read that at the top most point, the acceleration is STILL 9.8 m/s^2 where v=0 . The ...
0
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3answers
224 views

Deceleration of a bullet [closed]

Taking into account gravity, air resistance, and wind velocity and direction. (And also temperature if it's actually relevant.) I know the muzzle velocity, the total distance the bullet traveled, its ...
10
votes
4answers
7k views

What causes a soccer ball to follow a curved path?

Soccer players kick the ball in a linear kick, though you find it to turn sideways, not even in one direction. Just mid air it changes that curve's direction. Any physical explanation? Maybe this ...
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4answers
13k views

What is the general formula for a trebuchet?

What I'm really looking for is a formula for a trebuchet that I can input the desired initial velocity after launch and mass of the object, and from that figure out how long the long arm, short arm, ...
0
votes
1answer
43 views

Maximum displacement of a projectile with $x$ initial velocity and drag resistance

So, as a personal project, I imagined a scenario where a projectile with an initial velocity $x$ is affected by air resistance (drag) but not gravity, and I wanted to find out the distance it would ...
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2answers
976 views

What is the most efficient machine for translating gravitational potential energy of one mass into kinetic energy of a different mass?

As the question states, what is our current best machine for translating falling gravitational potential energy, such as a large weight, into launching a smaller projectile vertically? A lever? A ...
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3answers
76 views

Finding velocity from distance and gravity

Basically, I have a problem that asks: An object is launched to a height of 2 miles, what was it's initial speed and time. Now normally something like this would be fairly basic. The problem ...
1
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1answer
99 views

How relativity affects projectile motion?

If, for example, I'm in a train traveling on earth at $.99c$, and I drop a ball from a $1~\text{m}$ height inside that train how long would it take to hit the ground from the ball's frame of ...
5
votes
3answers
3k views

Finding optimal angle for projectile, taking into account linear (Stokes) drag

If you throw a projectile from the ground at a certain angle, it's not hard to see that, assuming we're in a vacuum, throwing it at 45º from the ground will always make it go farthest before it hits ...
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votes
1answer
57 views

Value of $g$ in projectile problems

A cannon has a muzzle speed velocity Vo of 60.0m/s, at what angle theta should it be aimed to strike a distance 320 meters away. Ignore air resistance So I get how to set this up but I am ...
0
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1answer
17 views

How would i go about deriving a formula to describe the projectile path of an object moving over a rotating ellipsoid?

The ellipsoid is rotating at a rate of $7.3*10^{-5} Radians/Second$. The height radius is $6.358*10^6 meters$ and the width radius is $6.3781*10^6 meters$. And gravity plays a large role because it ...
4
votes
4answers
7k views

Catapult vs. Trebuchet

I have been looking at trebuchet designs lately, and I have noticed that most, if not all, have a sling attached to them. Without such a sling, the machine would be a catapult. In terms of the speed ...
0
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1answer
537 views

x-coordinate of the ball when it's velocity is perpendicular to projection velocity

We have a ball projected at 20 m/s at an angle $\pi/6$ from the x-axis. Now we have to calculate x-coordinate of the ball when it's velocity is perpendicular to projection velocity. I am thinking ...
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1answer
155 views

Free-fall with linear drag

The standard first-course free-fall with linear drag situation posits a particle falling with a constant acceleration (typically due to approximation of gravity), but with a retarding force that is ...
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0answers
168 views

What is the time the ball is in the air if thrown at 14 m/s initially at an angle 57 degrees? [closed]

Julie throws a ball to her friend Sarah. The ball leaves Julie's hand a distance 1.5 meters above the ground with an initial speed of 14 m/s at an angle 57 degrees; with respect to the horizontal. ...
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2answers
443 views

Uniformly Accelerated Motion question

A ballast bag is dropped from a balloon that is 300 m above the ground and rising at 13 m/s. For the bag, find the maximum height reached. Now the book gives me this answer - $V_i$ = initial ...
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2answers
329 views

Motion of center of mass

I was reading about COM and forces and came upon this in my book. If a projectle explodes in air in different paths,the path of the centre of mass remains unchanged.This is because during ...