Questions tagged [projectile]
This tag is for questions relating to projectile, object moving through space due to the exertion of a force. The path of a projectile is called its trajectory.
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Can anyone suggest a calculation model for estimating the location of a dropped object falling from a height?
I'm trying to find models that allow me to calculate dropped objects, specifically, a model where I can consider lateral displacement due to wind force and vary the weight and resistance force of the ...
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How do rifled-bore shells remain pointing into the airflow?
I can understand the logic behind spin-stabilizing bullets, which travel only a few hundred meters on fairly flat trajectories.
But I cannot understand the logic for artillery. Won't spinning shells ...
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Calculate the speed of a rifle bullet as a result of shooting a bullet, should we use momentum or kinetic energy?
Say a rifle fires a bullet. We know the mass of the bullet, the velocity of the bullet (upon exiting the barrel) and the mass of the rifle. The rifle shoots hanging from a string, and we want an ...
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Does vertical coriolis force affect motions of projectiles?
If an object is projected towards east or west from the equator, we get the coriolis force to be vertical. If this projectile, say, miss its target from below, can this be attributed to the coriolis ...
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What causes an arrow to rotate? [duplicate]
My intuition:
In a system without air resistance, I would expect an arrow shot at an angle with its head pointing upwards to follow a ballistic trajectory without rotating around the horizon - because ...
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Problem with modelling a water rocket
I am trying to model a water rocket to find the optimal volume of water(without neglecting air resistance).
So, firstly, I make the assumption that throughout the journey of the rocket from t = 0 to t(...
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Dimensional analysis of particle falling against air resistance [closed]
I'm trying to solve a question in a sample exam paper. The student is asked to use dimensional analysis to find the time taken for a particle to fall a certain distance when drag is proportional to ...
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Why is it that we can consider the trajectory of an object in both directions and still get the correct answer? [closed]
Sorry for the unclear title. Here is the question:
why is it that we can "reverse the motion" as if the ball was being shot from the left and up towards the roof at the angle $\theta$? Is ...
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Will a ball spin in place if the friction force is high enough?
Pretty simple question. If we have a ball on a ramp with angle $ \theta $ and therefore a component of gravity acting along the ramp equal to $mg \sin(\theta) $ and a friction force that is exactly ...
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What is the practical speed limit for rail-gun orbital launches due to heat-generating wind resistance?
I was looking into the practicality of rail-gun technology to achieve orbital launches (As promoted by the answers at What is the possibility of a railgun assisted orbital launch? ), but found that ...
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Optimizing accuracy of different basketball shots [closed]
I have a high school math project and chose to work on basketball trajectory because I thought I would enjoy it the most. But honestly, I have a hard time calculating a 3D trajectory. So I thought ...
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3D projectile motion simulator with drag is not constrained to a 2D plane
This is an example of the problem. I've set the initial velocities to be $(x,y,z) = (100,10,100)$ and the drag-coefficient and CS-area to be 1.
As you can see the motion is not constrained to one ...
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How to calculate the point on a projectile motion where magnitude of displacement is largest? [closed]
In a homework question assigned by my physics teacher, he claimed that the magnitude of displacement always increases throughout the projectile motion. That can’t be true since if you throw at 90 ...
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How do I solve this projectile motion problem?
Everytime I approach any projectile motion/kinematics problem, I get confused. I don't know how to translate the problem into an operational method, and every time I complete a problem, the next one ...
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Why is the ratio of components of kinetic energy equal to the ratio of kinetic energy to total energy for a projectile whose range is maximized?
The launch angle $\theta$ that maximizes the range of a projectile in a uniform gravitational field is
\begin{align}
\theta = \arctan\left(\frac{v_o}{\sqrt{v_o^2 + 2gh}}\right), \tag{1}
\end{align}
...
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How to compensate for vertical displacement when calculating the $x$-velocity of a projectile with a fixed arc height? [closed]
My background
I'm working on a project for a client in the gaming industry. Newtonian physics and vector math is usually my forte, but I'm usually solving problems in directions opposite of what this ...
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${}$ Projectile motion
Basically we take the value of acceleration due to gravity as -ve ($-g$),when an object is thrown in the opposite direction of $g$. But in projectile motion the object first opposed the g and travels ...
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How do I solve for distance in the $x$ when only given the radiant velocity and the angle above the horizontal?
I recently had a physics test in AP physics one algebra based that my entire class failed. It was full of questions like this:
A projectile is launched from a level surface toward a cliff. At launch, ...
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What are the conditions that produce various shapes in 2D motion?
I have read that projectile motion is parabolic in nature. I know that the equation of projectile motion represents a parabola. But when do we get a parabolic curve? Does it happen when there is ...
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Why is the distance negative in a kinematic equations? [closed]
A rocket with zero initial speed takes off at a speed of 100 meters per second, assuming that gravity is 10 meters per second squared, determine the distance travelled:
$$ v_f^2 = v_i^2 + 2ay $$
...
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How does gravity do work to a horizontal projectile?
Suppose a ball is moving in a horizontal projection with some velocity $u_0$ in the positive $x$ direction. Here we see that although gravity is perpendicular to the velocity vector, it changes the ...
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Why does a long rectangular cardboard thrown in air start spinning automatically?
A long rectangular cardboard thrown in air starts spinning automatically on its way down. Few observations in this experiment:
Long rectangular cardboard pieces spin well
Doesn't work well with ...
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Confusion in the graph of displacement v/s time [closed]
A ball is dropped at $t=0$ from a height $h$ as shown, it collides elastically with the floor and rebounds to the same height. Draw displacement v/s time graph for the ball's motion taking downwards ...
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Which way does a stone move when hit by a wheel/tire?
I don't think this exact question has been asked before in the physics section. I am mostly interested in understanding it conceptually rather than calculation. I have asked the same question in the ...
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Variation of height above the ground and speed
A ball is dropped from rest and falls towards the ground. Air resistance is negligible. What is the graph that shows the variation with speed of the height of the ball above the ground?
Here's my ...
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Graph of acceleration against time?
Considering no air resistance, the acceleration time graph for a free falling object would be a horizontal line as the acceleration remains unchanged. When we do take into account air resistance, the ...
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How come shooter does not receive same energy as bullet (Newton's third law)?
So for example, a bullet weighting 7 g and going out of barrel at 420 m/s has ~617 joules of kinetic energy. So I'd think same would apply to shooter (or his hand specifically) - a 80 kg shooter would ...
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Why free fall motion is parabolic?
Consider no air resistance. If we throw a ball vertically upward from my point of view it goes vertically up and down and moving along straight line. But from point of view observer in outer space it ...
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When exactly is "just before hitting the ground"? [closed]
So it just hit me, "When is just before"? Cos just before could be a second ago or half a second ago or a tenth of a second ago and so on. So when? And do the final velocity formulas put ...
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How to calculate the trajectory of a high speed projectile on earth?
Let’s say you launch a high velocity ($2-8km/s$) projectile from the earth at the equator. How do you calculate the trajectory of the projectile in the absence of drag? Is there a simple formula that ...
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Could an egg theoretically be thrown like a boomerang?
I don't know exactly how boomerangs work, but I imagine that the fact that they are less symmetric than a sphere is part of the reason they can be thrown in such a way that they return to whomever ...
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Will spinning a bullet really fast without changing its linear velocity make it do more damage?
The damage caused by a solid projectile can be roughly approximated with its kinetic energy, since all of that energy will be dissipated into the target on impact (in an ideal scenario, ignoring ...
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How strong of a gravitational field do you need for a projectile to make a full loop?
How strong of a gravitational field do you need for a projectile to make a full loop? By full loop I mean it curves once around the by dot, and then it ends up on the same trajectory as it was one ...
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The motion of a ball thrown in a rotating frame of reference
Assume, there are 2 people staying next to each other on a rotating disk, s.t. there is a straight line from one to the other going through the center of the disk. One throws a ball to the other.
I ...
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Given that I know the initial speed, elevation and target location of a projectile, how do I find the launch angle? [closed]
I have a system where I know how far away a target is, the relative elevation and an initial launch speed with gravity, no drag. What I need to figure out is what angle (relative to the floor plane) I ...
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The solution of linear air drag and transcendental number $e$
I was watching a course about classical mechanics and in the chapter on air resistance the instructor wanted to show how transcendental numbers appear to the solution of linear air drag differential ...
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Numerical Method for solving Newtonian Equation of Motion for Particle experiencing drag in fluid flow
Currently, I have a fluid solver that can calculate the lift and drag forces acting on a body on a per timestep basis. This means that I have data regarding the hydrodynamic forces only for the ...
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Maximising spin on a table tennis ball: speed or acceleration?
In table tennis it is often desirable to produce as much spin on the ball as possible using a glancing contact. (The rubber covering of a table tennis bat is typically highly elastic and has a high ...
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Largest momentum a man can generate with his body? [closed]
With just the human body and no extra help (e.g. no gunpowder), what is the maximum momentum one can impart to an object?
As an example, the fastest a human has thrown a baseball (weighing 0.145 kg) ...
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Why does the angle for maximum range decrease in the presence of drag?
In the absence of drag, the angle to launch a projectile is 45°. In the presence of drag, the angle to attain max range is complicated. However, there seems to be consensus that it has to be less than ...
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Why doesn't the Coriolis force deflect incoming projectiles and rockets? [closed]
The calculation shows that at a distance of 10 km, the deviation due to the action of the Coriolis force will be more than 8 m, and at a distance of 20 km already more than 30 m, which is quite ...
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Vertical Projectile with linear air drag
If a spherical ball of mass $m$ is thrown upwards with an initial velocity $v_0$ and it experiences linear drag, how do we come up with expressions for $v(t)$ using Newton's second law (taking up as ...
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Shooting a bullet in motion
If a bullet is shot from a firearm from a moving car in the direction of movement, would the speed gained with respect to the car be same as the speed of a bullet that is shot from an immobile gun?
I’...
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Getting different angles of projection at different coordinates of projectile
I have been confused about this question on projectile motion for a while, and although I have managed to get solutions, I have not seen a resolution of my confusion. The question is:
The horizontal ...
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Kinematics problem involving two balls [closed]
I'm having trouble with a kinematics problem and was hoping someone could help me out. The problem goes like this:
"A ball is dropped from rest from a point P on a tree branch 5 m above the ...
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Projectile motion - Net Work and speed [closed]
I have proved this statement in multiple ways. Yet my intuitive proof goes against the mathematical proof: one must be wrong!
Statement
In a projectile motion with no drag, the magnitude of the ...
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Why does the gyroscopic precession of a spin-stabilized bullet cause drift in the same direction as the spin?
I am trying to understand the physics behind the gyroscopic phenomenon called spin drift. Spin drift occurs to bullets that are spin-stabilized over the course of their flight.
Spin drift starts with ...
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What should be the angle from horizontal (in anticlockwise direction) for which range is maximum for a projectile projected from a height?
I was studying about projectiles in the section of 2D Kinematics, where I came to know about the ground to ground projectiles. I got to know that for having maximum range in ground to ground ...
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Maximum height of bullet shot straight up [closed]
"Consider a hypothetical dense astronomical object with a mass of $2 × 10^{30}$ kg (about the mass of the sun), and a radius of $1.4 × 10^{14}$ m. Assuming you could stand on the surface of this ...
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Finding max range and speed at highest point of trajectory when projected Horizontaly
What is the maximum range of a shell projected across horizontal
ground from a gun with an initial speed of 300 m s-1? What will its
speed be at the highest point of its trajectory? (Ignore air
...
