# Tagged Questions

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

2k views

### A Basic Question about Gravity, Inertia or Momentum or something along those lines

Why is it that if I'm sitting on a seat on a bus or train and its moving quite fast, I am able to throw something in the air and easily catch it? Why is it that I haven't moved 'past' the thing during ...
10k views

### What are the precise statements by Shouryya Ray of particle dynamics problems posed by Newton which this news article claims have been solved?

This recent news article (here is the original, in German) says that Shouryya Ray, who moved to Germany from India with his family at the age of 12, has baffled scientists and mathematicians by ...
21k views

### Will a ball thrown straight up in a train land in same spot (in real world)?

I have a question that came up in a discussion with friends. If I throw a ball straight up in an enclosed train car moving with constant velocity, I believe the basic physics books say it will land ...
10k views

### Equations for an object moving linearly but with air resistance taken into account?

I know (from Kinematics) that for an object moving linearly with an acceleration and without air resistance the following equations can be used to determine v(velocity) or x(position of the object) at ...
2k 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? ...
2k views

### Put a bullet into orbit around the moon

While I was watching this beautiful video, the absence of air friction pushed me to ask myself: While standing on the surface of the moon, what is the initial velocity by which you can fire a bullet ...
66k views

### Solving for initial velocity required to launch a projectile to a given destination at a different height

I need to calculate the initial velocity required to launch a projectile at a given angle from point A to point B. The only force acting on the projectile after launch will be gravity – zero air ...
5k views

### Maximum range of a projectile (launched from an elevation)

If a projectile is launched at a speed $u$ from a height $H$ above the horizontal axis, and air resistance is ignored, the maximum range of the projectile is $R_{max}=\frac ug\sqrt{u^2+2gH}$, ...
644 views

### Is there an intuitive explanation for the Southward force caused by the Coriolis Effect on rotating spheres?

From the Coriolis Effect article on Wikipedia, the following with regard to the Coriolis Effect on a rotating sphere: By setting vn = 0, it can be seen immediately that (for positive φ and ω) a ...
3k views

I am given an initial x and y position and initial velocity and I was asked to graph the trajectory in 1 second intervals. This is what I have so far: If $x_0 = 1, v_{0x} = 70, y_0 = 0, v_{0y} = 80, ... 6answers 50k views ### Could someone jump from the international space station and live? Felix Baumgartner just completed his breathtaking free-fall skydiving jump from$120,000\,\text{feet} = 39\,\text{km}$above the Earth, breaking the speed of sound during the process. I was wondering ... 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 ... 4answers 6k 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 ... 3answers 2k views ### Intuitive meaning of factor 2 in formula of vertical throw max height$h=v^2/2g$This is a question about a simple thing. The simplified expression for maximum height in vertical throw is$h=\frac{v^2}{2g}$, could anyone explain intuitively (analogies are welcome) why there is a ... 2answers 1k views ### The angle of launching an Angry Bird that will land the bird furthest from the launching point is 45 degrees? This is a question motivated by Angry Birds. When playing the game, I notice that if the initial velocity is constant, the way to land a bird furthest away from the launching point is by launching ... 1answer 3k views ### 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 developer and I am working on a ballistics calculator for rifles. I am using wiki for the trajectory ... 8answers 4k views ### Real world examples for projectile thrown upwards or downwards I am preparing a physics course for high school about projectile motions. If a projectile moves with initial velocity$v_0$in the gravitational field of the earth, the equation $$s(t) = 1/2 g t^2 ... 2answers 145 views ### Kinetics energy with different reference frame (a fighter plane shoots a bullet)? Let say a plane flights at 1km/s, shoots a 2kg projectile at 1km/s, so to the Earth, the projectile flights at 2km/s with 2*2*2/2 = 4MJ. The same gun when fixed on Earth, shoots the same 2kg ... 2answers 244 views ### Estimating atmospheric friction by measuring the change in velocity of a ball thrown straight upwards Imagine I throw a ball straight upwards with some velocity v_1, and filming the ball with a camera, I can estimate a velocity v_2 (along the same vector) after the ball has moved a distance D. ... 1answer 784 views ### Time of a ball going up and down with air resistance A ball is shot directly upward, and then it comes back to the place where it was shot. Suppose we have air resistance. Suppose t_1 is the time period from the moment that the ball was shot to the ... 1answer 3k views ### Trajectory of projectile thrown downhill I'm teaching myself mechanics, and set out to solve a problem determining the optimum angle to throw a projectile when standing on a hill, for maximum range. My answer seems almost plausible, except ... 3answers 342 views ### Why is the range of a projectile proportional to the square of the initial velocity? I was watching the MIT lecture about projectile motion and the lecturer asked why$$D=\frac{(v_0)^2\sin(2\alpha)}{g}$$Why is it$(V_0)^2$not$V_0$? It is a hypothetical question i know that the ... 2answers 2k views ### Is Magnus effect a corollary of Bernoulli principle? Magnus effect is commonly explained using Bernoulli principle. However, taking the lift on a rotating cylinder as an example, the velocity difference is caused by the extra work done by the rotating ... 2answers 2k views ### Kinematics - projectile motion on inclined plane [closed] Well I've tried everything to solve this problem, spent well over an hour, and have gotten no results. A particle is thrown over a triangle from one end of a horizontal base it grazes the top vertex ... 2answers 2k views ### Throwing a ball upwards in an accelerating train If I throw a ball upwards to a certain height in an accelerating train, will it end up in my hand? At the moment I release the ball, it will have a velocity equal to that of the train at that instant. ... 1answer 2k 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 ... 2answers 1k 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 ... 2answers 206 views ### A big cannon to match a ballistic missile? [closed] During the last years of WW2 the Germans used ballistic missiles V-2 (with payload mass ~1,000 kg) to bombard London, from a distance about 300 km away. Suppose the British could respond by building a ... 1answer 3k views ### What is the maximum efficiency of a trebuchet? Using purely gravitational potential energy, what is the highest efficiency one can achieve with a trebuchet counter-weight type of machine? Efficiency defined here as transformation of potential ... 7answers 1k views ### What happens when the spacecraft velocity equals the velocity at it's exhaust? So there I was resting me eyes thinking about rocket drives, and what-not. The thought struck me that, perhaps, even before Mr. Einstein interferes with the increasing velocity of the spacecraft Mr. ... 4answers 4k views ### How Felix Baumgartner has reached the speed of sound quickly I have watched Felix Baumgartner freefall; but I wonder how Felix has reached the speed of sound quickly, in a matter of some seconds, then we had no idea of its speed? Any explanation please. 1answer 405 views ### If a bullet is fired vertically upwards, when it comes back does it fall to the same spot? What I'm basically asking is that if a body is projected with sufficiently high velocity so that it doesn't escape from the earth's gravitational field but reaches an appreciable height with respect ... 1answer 150 views ### What is the force required to move a raindrop? I'm doing some research on how much force is required to move a typical raindrop (assuming that it is falling straight down) off to the side of X distance. This is for a school project on creating our ... 3answers 373 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 ... 1answer 76 views ### Effect of small changes in atmospheric pressure on open cylinder piston OK, I'm not a physics student, but I played one for 2 semesters 35 years ago... now I'm a competitive shooter working a theory about why small changes in atmospheric conditions cause our hyper-tuned ... 3answers 1k 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. 3answers 1k 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 ... 1answer 96 views ### What is the point of this type of graph? (Projectile) [closed] What is the point of graphing vs range, during kinematic motion? 1answer 78 views ### Falling metal cylinders more devastating than a nuke? I just saw G.I JOE - Retaliation. In the movie the bad guys (spoiler alert) Could this device cause more destruction than a nuclear weapon? If so, how? 5answers 4k views ### How to get the angle needed for a projectile to pass through a given point for trajectory plotting [closed] I am trying to find the angle needed for a projectile to pass-through a given point. Here is what I do know: Starting Point$(x_0,y_0)$Velocity Pass-through point$(x_1, y_1)$I also need to ... 2answers 1k 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 ... 1answer 90 views ### What makes the equations of motion dependent on each other? When Galileo put forward the proposition that the motion of a projectile analyzed into separate horizontal & vertical parts, he made a great contribution to the conceptual basis of mechanics. ... 2answers 546 views ### Free fall and projectile motion I'm wondering if something is falling say from a roof, would the distance it falls be the final$y$position? Also would all the$y$components (velocity, displacement) be negative? 0answers 21 views ### Two Dimensional Kinematics and Projectile motion [duplicate] I have a question. So a baseball is hit with a velocity of 30 m/s at 42.6 degrees to the ground. A fielder who is supposed to catch the ball is smart and knows that he is exactly 8 meters from where ... 2answers 129 views ### Ice throw from industrial wind turbine I was watching a documentary where the residents didn't want to have a wind turbine erected nearby. One of the comments from the company was that an ice throw would have very little importance since ... 2answers 335 views ### Maximum range for projectile thrown from a mountain [closed] I have doubts with the following problem: A projectile is fired from the top of a mountain that has a downward slope with angle$\phi$from the horizontal. The initial velocity of the projectile is ... 3answers 6k views ### Solve for Initial Velocity of a projectile given Angle, Gravity, and Initial and Final positions? I've found equations http://www.physicsclassroom.com/Class/1DKin/U1L6a.cfm for solving everything (and rearranged to solve everything) to do with projectile motion EXCEPT this, even though it should ... 2answers 518 views ### Aerodynamic drag on a cannonball? I'm trying to build a ballistics simulation where I shoot a cannonball. I want to allow for drag and am trying to work out the math to do so. I can work the drag out using$F = C_d\times S\times ...
Studying formulas about velocity and acceleration I came up with a question: if I throw an object in the air with a velocity $v_0$ (suppose i throw it vertically) in how much time its final velocity ...