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

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146 views

Parabolic Motion

I was wondering if I was right about this simple problem: A projectile is shot at an angle of 37.0° with the horizontal. The velocity of the projectile at its peak height is 16 m/s. Then I was told ...
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2answers
2k views

Bullet trajectory at different angles

I've read from different sources (can't find them online) that firing a bullet at different angles from horizontal will result in differing amount of bullet drop. For example, a gun is fired at a ...
2
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2answers
389 views

Mass Effect on Slingshot Motion?

For my physics class (I'm a high school student), we created slingshots. Our task is to predict the distance a projectile, launched from a slingshot using surgical tubing, would land. We aren't given ...
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3answers
886 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 ...
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3answers
743 views

In projectile motion, what does it mean for the motion along the $x$ and $y$ axis to be independent?

In projectile motion, what does it mean for the motion along the $x$ and $y$ axis to be independent? This question is referring to the concept of projectile motions.
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3answers
139 views

How can I modify the bullet trajectory based on the ballistic coefficient? [duplicate]

Possible Duplicate: How to modify the bullet trajectory based on the ballistic coefficient? I am new to the physics surrounding bullet trajectory and how it is calculated. I am a software ...
2
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1answer
162 views

Is there a better, faster way to do this projectile motion question? [closed]

The question is In a combat exercise, a mortar at M is required to hit a target at O, which is taking cover 25 m behind a structure of negligible width 10 m tall. This mortar can only fire at an ...
2
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2answers
771 views

Conservation of momentum when friction is present

Conservation of momentum applies when net force is zero. Suppose that there is a system of a canon and a canonball. Total momentum of the system is zero before canonball is fired. Now canonball is ...
2
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1answer
235 views

A bumpy ride on a bike?

While riding a bike at a higher velocity, I go over the speed breakers (Hump) I get jumped over the bike for a certain height. How do I calculate this height of jump with respect to the seat of the ...
2
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2answers
176 views

Parabolic motion (experiment)

We performed a laboratory, performing six releases of a sphere with angles $15^\circ,30^\circ,45^\circ,60^\circ,75^\circ,40^\circ$ a parabolic movement, took five distances for each angle, the initial ...
2
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1answer
234 views

Galilean relativity in projectile motion

Consider a reference frame $S^'$ moving in the initial direction of motion of a projectile launched at time, $t=0$. In the frame $S$ the projectile motion is: $$x=u(cos\theta)t$$ ...
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3answers
564 views

What is the general approach to calculating time of impact in 3D?

Given two objects a and b moving at fixed velocities, how would you determine (a) whether they will collide at all, and if so, (b) time of impact? (Let us assume these are spherical bodies each with ...
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1answer
1k views

The trajectory of a projectile launched from a hilltop

Here is the problem: A boy stands at the peak of a hill which slopes downward uniformly at angle $\phi$. At what angle $\theta$ from the horizontal should he throw a rock so that it has the greatest ...
2
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2answers
620 views

How to calculate a firing location from point of impact data?

I would like to know how to calculate the point at which a bullet is fired from a gun given information from the scene where the bullet falls. The scene would contain the point of impact (GPS ...
2
votes
1answer
395 views

Realistic projectile motion

I am working on a project involving a simulation of the motion of a projectile (in 3D) aimed at a moving target. The way projectile motion is analyzed in most introductory physics books is not ...
2
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1answer
935 views

Ski Jumper's vertical velocity after $246.5m$ record?

What would be the vertical velocity of this ski jumper (ski flyer), after he first touches down, after he breaks the record with a $246.5m$ jump? What g force would he experience as he slows down? ...
2
votes
2answers
59 views

Deceleration rate of objects of different mass but the same otherwise

Using a tennis ball as an example object, if one ball weighs 1 ounce and the other is 2 ounces, and both are struck at 100 mph on the same trajectory, would there be any difference in the deceleration ...
2
votes
1answer
54 views

Kinematic, motion in 2D [closed]

If the kinetic energy at maximum height is 2/5 the kinetic energy at half the maximum height, find the angle of projection. In other words: K.E. at H(max) = 0.4*K.E. at 0.5*H(max) I got 60 degrees, ...
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2answers
162 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 ...
2
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1answer
71 views

Is the resistance 0 in the ballistic regime?

Given that in the ballistic regime a particle (electron) can move freely without scattering (there are no impurities ), is the resistance through a ballistic sample zero?
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0answers
252 views

Projectile motion equations @ very (!) high starting velocity

I've already searched Physics StackExchange for some similar question but I didn't find anything about this. Assumptions: Earth is a perfect sphere with it's core (X,Y,Z) -> (0,0,0) as a ...
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4answers
798 views

Projectiles and escape velocity [closed]

Q: The escape velocity for a body projected vertically upwards from the surface of earth is 11 km/s. If the body is projected at an angle of $45^\circ$ with vertical, the escape velocity will be? ...
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1answer
80 views

Why does a difference in approach to projectile motion yields different results?

A body is projected vertically upwards from the surface of the earth with a velocity equal to half the escape velocity. If $R$ is the radius of the earth, then find the maximum height attained by the ...
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1answer
2k views

Simple Projectile Motion Question

A volcano erupts 50m below the sea level. A rock leaves the crater at 20 m/s at an angle 30 deg with the vertical line. The rock has a mass of 15kg. IGNORE WATER RESISTANCE. It gets out of the water, ...
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3answers
579 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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4answers
103 views

Is it possible to prove that projectiles with drag will not travel in a parabola under the theory of classical mechanics?

Can you prove that projectiles will travel in a parabola, provided the acceleration due to gravity $g$ does not vary significantly along the trajectory? This should take air resistance into account. I ...
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1answer
44 views

Minimize initial velocity of projectile to arbitrary point

I'm supposed to shoot a projectile from the origin to a point $(x_0 , y_0)$ with minimal initial velocity $v_0$. (no air resistance; regular gravity) The flight time should be $T=\frac{x_0}{v_x}$. ...
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1answer
93 views

Dropping an object from a plane [closed]

I've done this before, but it's been a long time. Using trigonometric functions, I've been asked to solve the following problem. However, I'm at a complete loss as to how to do it. I have 5 questions ...
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1answer
250 views

If someone shoots a gun (45 caliber) at someone holding up a table or desk 10 feet away, does it slow or turn the bullet away?

Assume it's a standard .45 caliber handgun. Shooter is 10 feet away, and we hold a desk, mini-table, blackboard, etc on our chests(to protect vitals). How do you figure out the bullet's decrease in ...
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1answer
223 views

3D ballistic trajectory with quadratic drag. Calculating position and velocity at time $t$

A particle starts at the origin and has an initial velocity represented by a 3D vector. The particle experiences gravity and air resistance with quadratic drag (based on velocity^2). What I've been ...
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2answers
100 views

Can a bullet leave a gun and tumble to the ground?

This question seems to have been asked a few times in different configurations, but none of them answer my variation. I've struggled to understand this for nearly 15 years and had conflicting answers ...
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1answer
179 views

Math / Physics Help - Barrel Pressure and Velocity

Back in 1993 I derived the following equations to calculate projectile velocity and barrel pressure. Recently, I have noticed that I need to double the calculated results in order to obtain real word ...
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2answers
644 views

Projectile Motion Question involving a ball and a ramp inclined at an angle

The question is to finde the initial horizontal velocity of the ball at end of the ramp, where it is released. I know how to do this using gravitational potential energy and kinetic energy ...
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2answers
889 views

Work done in projectile motion

A projectile is shot at some inclination to the ground. It falls at another point having R distance from the initial point on the ground. Is there any work done? If initial velocity vector is $(u\cos ...
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1answer
397 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 ...
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4answers
5k 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, ...
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1answer
120 views

Would a projectile keep going forever in empty space?

Would a projectile fired in space and assuming there were no stars or planets in the way, would the projectile continue on to infinity, since the x-component of the projectile's velocity never changes ...
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1answer
73 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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1answer
118 views

A ball is thrown up, and a second ball is dropped- what is the maximum initial velocity of the first ball so that

This question only exists in one dimension, the y axis. A ball is thrown upwards with an initial velocity $V_o$ from a roof with height $h$. One second later, a second ball is dropped from the same ...
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1answer
70 views

How jet engine works in vacuum

Its not about availability of oxygen for combustion of gases. I want to know since there is no air or friction providing things in vaccum, how the force applied by a jet engine get can make thrust to ...
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2answers
134 views

What decides the velocity of a bullet coming out from the gun?

I was concerned about what determines the speed of the bullet coming out from the gun. Is it determined by the strength of the explosive or how fast does it burn up? For example if we take the same ...
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1answer
217 views

1D Motion under Gravity

I have attempted this question in so many different ways but I am getting nowhere. Could someone point me in the correct direction so I can work it out myself? Here is the question: An object $K$ ...
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2answers
468 views

How can I solve for time without knowing the vertical velocity?

A guy posted this problem on a forum: There is a bird sitting on a pole of height h. you throw a rock at it and the moment the rock leaves your hand the bird starts flying horizontally away from ...
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1answer
275 views

Projectile motion in two and three dimensions question?

So I bought this book in the library and physics fascinates me and I found this quote in the book " Galileo has proved that when any effects due to air resistance are ignored, the ranges for ...
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2answers
208 views

Estimating atmospheric friction by measuring the change in velocity of a ball thrown straight upwards

Imagine I throw a ball straight upwards with some velocity $v_1$, and filming the ball with a camera, I can estimate a velocity $v_2$ (along the same vector) after the ball has moved a distance $D$. ...
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2answers
483 views

Kinetic Energy of Stone

If a stone is launched upward, of which is subject to gravity and air resistance, which of the following will have a greater kinetic energy? The stone at a point on its way up, or the stone at the ...
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2answers
357 views

Projectile Motion

I know the angle at which a projectile is launched, how far it needs to go, and also the maximum height. How can I find the initial velocity needed (disregarding air resistance)? Currently, I am ...
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1answer
159 views

Is it theoretically possible for the orientation angle of a projectile to remain exactly equal to the orientation of velocity?

This question is sparked by my answer to this question: Is this simulation following real physics? After examining the math, I don't see how it is theoretically possible for the situation simulated ...
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2answers
63 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
74 views

Upthrust vs Drag

24: A ball is falling at terminal speed in still air. The forces acting on it are upthrust, viscous drag and weight. What is the order of increasing magnitude of these 3 forces? ...