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

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2answers
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Why can a ball tossed up object free fall upwards?

I've found many websites that say that a ball tossed upward would be free falling upwards, but none of them say why. If the definition of free fall is an object that is falling while only under the ...
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1answer
124 views

Deviation from 2D trajectory [closed]

I need to find out how far a ball is from the predicted trajectory in 2 dimensional space and I know the start and end position of the ball in both dimensions. Along with that I know the initial ...
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3answers
295 views

Why is the constant velocity model used in a projectile motion derivation?

I was re-studying university physics last week, I'm now in the chapter about kinematics in 2 dimensions and specifically the one treating projectile motion. In page 86 of his book (Serway - Physics ...
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1answer
135 views

Is speed squared constant?

q. A heavy particle is projected at speed $U$ at an angle $\alpha$ to the horizontal. The particle is subject to air resistance which is experimentally found to vary proportionally to the square ...
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2answers
135 views

How do I properly write Newton's second law for a particle with drag?

A heavy particle is projected at speed $U$ at an angle $\alpha$ to the horizontal. The particle is subject to air resistance which is experimentally found to vary proportionally to the square of ...
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1answer
87 views

Some subtleties in direction of drag force

Consider a body released from a height $h$ and assume a drag force is linearly proportional to the velocity. Then by Newton's Second Law, $$m\mathbf{\dot{v}} = \mathbf{F_g} + \mathbf{F_{drag}} = ...
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1answer
410 views

Projectile motion of a charged particle in a homogeneous electric field

I'm reading an article about projectile motion, but I'm having some trouble with how the author found the equations of motion when a homogeneous electric field is considered. To allow an immediate ...
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1answer
168 views

Calculating Mass for a Reduced Trajectory while Keeping Projectile Force Constant

Apologies if this is not a research-specific question, but applied mechanics. A firefighter has to pass a test in which he is to throw a medicine ball a certain distance. The ball is thrown at a 45 ...
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2answers
907 views

Monkey and tree - projectile motion

The famous scenario: A hunter is trying to shoot a Monkey hanging from a tree. However, this question doesn't mention the monkey jumping down from the tree or trying to escape. (The hunter uses a ...
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1answer
225 views

Idealized trajectory from sloped surface

I am a GIS programmer implementing a visualization. I am modeling the idealized trajectory of a particle ejected from a volcanic vent using: $$\text{distance} = \frac{(v^2 \times ...
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3answers
3k views

Projectile Motion with Air Resistance and Wind

I am wondering how the general kinematics equations would change in the following situation. If an object were fired out of a cannon, or some sort of launcher, so that it had both an initial velocity ...
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1answer
3k views

Friction due to air drag at high speeds

I am trying to set up this problem, but I am not sure how to go about doing so. (From University Physics, Young & Freedman): You throw a baseball straight up. The drag force is proportional to ...
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1answer
1k views

Simple projectile motion problem [closed]

A person wants to throw an object from the top of a tower $9,0m$ high towards a target which is $3,5m$ far from the place where the person is launching the object. Suppose that this object is thrown ...
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1answer
3k views

Trajectory of projectile thrown downhill

I'm teaching myself mechanics, and set out to solve a problem determining the optimum angle to throw a projectile when standing on a hill, for maximum range. My answer seems almost plausible, except ...
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1answer
10k views

How to find maximum velocity

I stack a question about projectile question. The question was A projectile is being launched from ground level with no air resistance. You want to avoid having it enter a temperature inversion ...
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2answers
2k views

Projectiles problem solving

I've only learned about to use kinematics equation when solving projectile problems but today i came across the following equations. where does they come from? Distance travelled Time of flight ...
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0answers
16 views

Projectile motion. Scattered trig ratios, unable to condense [closed]

I have this question from university to complete: A rugby player kicks a ball from the ground aiming to get the ball over the horizontal bar and between the vertical posts. The ball is 50 meters away ...
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0answers
22 views

Find the maximum height, distance from the launching point and the time in which a rocket has been flying? [closed]

A rocket is thrown at an angle of $53$ $degrees$ with the surface of Earth, with initial velocity $100 m/s$ and initial acceleration 30 $m/s^2$. The engine works only for $3$ seconds then rocket acts ...
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0answers
48 views

Calculate ballistics using Pejsa method (bullet physics)

I'm not sure if it was already asked, but, could someone please explain the Pejsa method of ballistics, specifically the velocity and trajectory (no energy, wind or lead etc.) (just drop drift and ...
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0answers
36 views

Maximizing horizontal displacement from projectile motion off of downward slope [closed]

Firstly, I think I should point out that I am a high school student, so please excuse me if my question seems mediocre. What I am doing was seemingly simple, I am doing some research on projectile ...
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0answers
19 views

Bullet - Jet problem, How to equate horizontal displacement. projectile motion [closed]

A jet is moving hotizontal with speed of 720km/h at height 1960m . when it passes above point on ground at same time bullet is fired from that point with velocity 400m/s I want to know the angle from ...
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0answers
30 views

Find the angle of the projectile [closed]

Given: Hmax = 2 * Range Find the angle of the projectile. After using the formula for both Hmax and Range, I got an angle of 74.69 if I am not mistaken. On the math exam teacher said the answer ...
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1answer
34 views

How fast does a long object bent at the center need to be travelling in order to boomerang?

At an angle, of course. Standard pressure, average temperature, and calm wind. Bonus question: Can an object that is not bent boomerang at all? If yes, how different would the equations for this ...
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0answers
28 views

Is there a way to find the optimal angle to launch an object to get maximum distance when there is an initial height? (Projectile motion) [duplicate]

I know that the optimal angle to launch an object at ground level is 45 degrees; however, i want to know that if there is anyway to get the optimal angle to launch an object to get the maximum ...
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0answers
21 views

How do I determine the amount of time an object is in the air given these variables? [closed]

An object is thrown straight up from 2 meters above the ground. Its apex is 8 meters. How long is its flight? I don't understand how this question can be answered so if anyone can give me a detailed ...
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0answers
63 views

Projectile motion and drag problem [closed]

I am currently working on an artillery simulation but I came across a problem: I require an equation that will give me the required initial angle when given a velocity the range and elevation, ...
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0answers
35 views

Maximum possible acceleration value on a ball in volleyball game

I have been examining this subject on web but could found enough information yet. I have to make a decision on choosing "range" for accelerometer which will measure acceleration value of ball in ...
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0answers
40 views

Free Falling Bodies [closed]

An object is thrown vertically upward. It has a speed of 10ft/s when it reached one-half its maximum height. since this is a thrown object it's initial velocity is a mystery, is it right to make ...
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2answers
192 views

Projectile motion - calculate landing angle

A projectile is launched at a $45^\circ$ angle, aiming for a target at a distance of 15 feet away from, and $2$ feet below the starting position. I'm looking for equations to determine: The ...
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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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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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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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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 ...
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2answers
272 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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0answers
167 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
51 views

Projectile motion velocity [closed]

If a projectile breaks into two pieces at the highest point of its trajectory and one of them retraces the same path, why will that piece have the same magnitude in velocity as the whole projectile?
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1answer
98 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 ...
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0answers
90 views

Projectile Motion [closed]

I've spent some time pondering the answer to this equation, without any success. A cannon is arranged to fire projectiles, with initial speed $v_0$, directly up the face of a hill of elevation angle ...
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2answers
458 views

Projectile, air resistance and wind

So for my school project I am working on a projectile simulator and air resistance. So I have looked at this. Equations for an object moving linearly but with air resistance taken into account? ...
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1answer
79 views

Newton's law of resistance [closed]

Anyone can give me some clues on how this can be proved? What kind of drag force is used? A particle is projected vertically upward with an initial speed $v_0$ near the Earth's surface. Show that ...
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1answer
96 views

Will a heavier or lighter tank shell / bullet/ etc. travel further given the same starting energy?

Let's say I have for example two tank shells, both being the same size and having the same shape. Let's say the starting energy is 100kg*m/s^2, and the one shell is 1kg, the other 25kg. 1kg * ...
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0answers
125 views

Projectile motion, solved with perturbation theory [closed]

A ball is dropped from rest, the initial height is $h_1$. There is air resistance given by $-mkv$. In the downward motion, the equation of motion can by written as $$\dot v = -g-kv$$ with the y ...
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1answer
74 views

How to find the maximum height with a loss of 5 J of energy due to air drag [closed]

Can someone please help me to figure out how to use the 5J of energy into my equation for the maximum height. I know that the maximum height is given by, $$h_{max}={(v_f-v_i)^2 \over 2g}$$ but I'm ...
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0answers
82 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.
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1answer
408 views

A ball is dropped from the roof of a building. How fast is it moving after 4.9 seconds? (Absolute value) [closed]

i really need help. A ball is dropped from the roof of a building. How fast is it moving after 4.9 seconds? (Absolute value) in m/s A water balloon is thrown downward from a tall building with an ...
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2answers
3k views

Projectiles Launched at an Angle with unspecified Initial Velocity [closed]

I'm attempting to do my Physics homework, and I did the first one right, but that problem gave me initial velocity. This problem gives me only the angle relative to horizontal and the distance it ...
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0answers
151 views

Projectile Motion Equation - Understanding this Formula [closed]

I don't understand why this formula is relevant to the problem: This was the relevant worked solution: My problem is that I do not understand this formula because I don't even understand what ...
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0answers
646 views

What is the angle of projection when at maximum height the speed of a projectile is half the speed at half the maximum height? [closed]

I have been struggling with this problem: The speed of a projectile when it reaches its maximum height is one half of its speed when it is at half its maximum height. What is the initial ...
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0answers
93 views

How to find the force to cause certain trajectory? [closed]

So I got a little board today and decided to do some physics. What I came up with is confusing me alot. Say someone throws a rock and when this happens you get the known's of. From here is there a way ...
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0answers
51 views

Why is more angular momentum required to stabilize the orientation of a heavier bullet?

It's often stated that "heavier" bullets require more "spin" to stabilize vs. "lighter" ones. My question is whether this is really a matter of mass. I'm assuming that the destabilizing ...