Initial velocity Definition and 451 Threads

Homework Statement An arrow shot into the air has a time of flight of 6s and a range of 210 meters. Find the: A.) Initial Velocity and B.) The angle at which it was shot. Homework Equations none? The Attempt at a Solution I don't know how to solve this.

Homework Statement Rock A is thrown straight up from the top of a 25m tall building at a speed of 20m/s. Exactly 1 second later Rock B is thrown in such a way that it lands on the ground at the base of the building at the same instant that Rock A lands. What is the initial velocity for Rock...

Homework Statement An applied force of 10.0N acts horizontally on a 0.50kg mass on a floor with the coefficient of friction being 0.40. If the object had an initial speed of 2.00 m/s, determine its speed at 15.0m. Homework Equations General Energy Conservation Formula Ek(i) + Ep (i) +...

Hey, I came across this question in my textbook, and there isn't an answer for it in the back, so I would just like to check if I have my head around it. The question is: 2 projectiles are launched at the same angle. Projectile 1 reaches a max height of twice that of the projectile 2. What...

Homework Statement I need to find Vi, knowing the following: Δt=6/Vi cos40 Viy=Vi sin40 Δy=4m ay=-g = -9.8m/s^2Homework Equations Quadratic: x= [-b +/- √(b^2-4ac)]/2a Kinematic equation to be used: Δy=ViyΔt + 1/2ayΔt^2The Attempt at a Solution Δy=ViyΔt + 1/2ayΔt^2 4=(Vi sin40)(6/Vi...

How to find the initial velocity required for a projectile to be launched at an angle theta, with a distance 'd' and height 'h'. An expression is required. I am unable to find one using all three. Thanks in advance.

Homework Statement A 10 g ball going at a speed of 5 m/s is kicked, and flies off at an angle of 35° at 25 m/s. What was the force of kick? Known: m = 0.0010 kg vi = 5 m/s θ = 35° vf = 25 m/s Homework Equations mvi = mvf F = ma The Attempt at a Solution Would this count as an...

Hi All, It's been a looong time since I've had to use/apply basic physics but I'm hoping I've come to the right place for help. I am trying to help my brother-in-law with a speeding charge. First question The police allege he reached 100km/h within 38m of a corner. The first...

So the question I'm asking about is actually from my analytical mechanics class, but I think my question is really more of a gen. physics question. Basically, in this question we have a cannon ball, diameter(EDIT:but not mass!), fired with a given muzzle velocity, and we are given the cannon...

Hi I need to find the horizontal distance traveled by an aircraft just after take off to a vertical height of 10.7m. The rate of climb is 1920m/min. I'm not really sure how to approch this question. I think simply it would look like a right angles triangle, I would need an initial velocity...

Homework Statement A 20.00kg curling stone is released at the hog line and moves 28.35m [W] to sit on the button and score a point. If the coefficient of kinetic friction between the stone and the ice is 0.0020000, what was the initial speed of the stone ? So we know: m=20.00kg...

Homework Statement A student is determined to test the law of gravity for himself. He steps off a skyscraper 320m high, stopwatch in hand, and starts his free fall. Five seconds later, superman arrives at the scene and dives off the roof to save the student. What must superman's initial...

Homework Statement An arrow is shot at an angle of θ=45* above the horizontal. The arrow hits a tree a horizontal distance D=220m away, at the same height above the ground as it was shot. Use g=9.8m/s^2 for the magnitude of the acceleration due to gravity. Find t, the time that the arrow...

Homework Statement A block is given a push up an inclined plane with an initial velocity. At what time will the speed of the block be equal to the initial velocity again? No varialbes are given. Homework Equations v= v(initial) + at The Attempt at a Solution The final...

Homework Statement A woman running at constant velocity speeds up and accelerates uniformly to the west by running 253 m west in 6.12 s. ff she ends up getting up to a velocity of 5.05 m/s w, how fast was she going originally? If she had run the same disance in 5.50 s, what would her average...

Homework Statement A ball is shot from a slingshot and clears a 10 meter fence 130 meters from the point of being flung and lands 10 meters behind the fence. What is the initial velocity of the ball? Assume the ball was caught at the same level it was kicked (delta Y=0). Homework...

Homework Statement A 50.0kg skier starts at A with an unknown initial velocity. The skier then goes over a hill (point B) which is 4.00m above point A. At point B (top of the hill), the skier experiences a Force normal 5/6 of his/her weight. The hill has a radius of 14.6m. What is the...

Because of the kinetic energy and frames of reference thread: https://www.physicsforums.com/showthread.php?t=534883 I was wondering how to show that a change from potential to kinetic energy in a closed system is independent of the (inertial) frame of reference. I think the math below...

I'm trying to help a friend with a physics problem. I've been helping her figure a few out(I always make sure she solves them and understands how she did) but we've hit one that's gotten us both stumped, so I'd appreciate a bit of assistance. The problem is basically, a Diver dives off a...

Homework Statement See image Homework EquationsSee image The Attempt at a Solution I have tried, but I honestly have no Idea how to start this problem.

Homework Statement A child operating a radio-controlled model car on a dock accidentally steers it off the edge. The car's displacement 0.77 s after leaving the dock has a magnitude of 7.4 m. What is the car's speed at the instant it drives off the edge of the dock? @t = .77s displacement is...

Homework Statement Material ejected to a height of 2.00 x 10^5m. Acceleration of gravity is 1.80 m/s^2, find initial velocity Homework Equations v (zero) = v - at. The Attempt at a Solution Seems as though I am missing something since I don't have time or velocity, yet I have...

A cannon sends a projectile towards a target a distance 1210 m away. The initial velocity makes an angle 26o with the horizontal. The target is hit. The acceleration of gravity is 9.8 m/s2 . What is the magnitude of the initial velocity? Answer in units of m/s y = viy•t +0.5•ay•t2 vix =...

Hi I need some help with this question: Estimate the maximum initial velocity you can achieve with a tennis ball I thought of using the maximum range formula: R=v2/g but doesn't that imply to the fact that I'm throwing at an angle of 45 degrees? Please help me, I really want to solve this...

Hello all, I got this question off mastering physics and was unable to understand it. I eventually gave up to concentrate on other assignments and asked for the answer. I was unable to come up with more than one answer I thought possible without resorting to trial and error. Answer: Vx,Vy,Vz =...

Homework Statement A juggler throws a ball just so it reaches the ceiling at 3.0 meters. (3m above hand) How do I solve for initial velocity? Homework Equations The Attempt at a Solution

How can you let Initial position and initioal velocity be equal to zero? I understand that it will be zero at time = 0, but as time goes on from 1, 2 , 3 , 4 won't it change? I underlined that it in read in the picture?

Ok so having a little problem with this one and i feel like its easier than what i am seeing, but just not sure how i can get a V-initial from this (Replaced actual numbers with AAA and BBB because i am trying to recall how to do all this, hope ya'll don't mind variables to much lol) The...

Homework Statement The position x of an object as a function of time is given as x = 2.257 + 4.894 t + 16.5 t2. All quantities are understood to be quoted in SI units. What is the initial velocity ? Indicate with a negative (positive) sign whether the acceleration is constant (not constant)...

Homework Statement At time t = 0, a car has a velocity of 16 m/s. It slows down w/an acceleration given by -0.50t in m/s^2 for t in seconds. It stops at t =? Homework Equations The Attempt at a Solution v = 16 - 0.5t 16/.5 = t 16 x 2 = t 32 = t Did I set this up wrong? My...

Homework Statement The "hang time" of a punt is measured to be 3.50 s. If the ball was kicked at an angle of 69.0° above the horizontal and was caught at the same level from which it was kicked, what was its initial speed? (Neglect air resistance.) Homework Equations All Kinematics...

Hi, I need to calculate the magnitude of the initial velocity of the following data for projectile motion. Any help would be greatly appreciated as I have no idea where to start! Thanks please see the question here: http://i52.tinypic.com/15p0kza.png and the data here...

Hi, I need to calculate the magnitude of the initial velocity of the following data for projectile motion. Any help would be greatly appreciated as I have no idea where to start! Thanks please see the question here: http://i52.tinypic.com/15p0kza.png and the data here...

hi there, i'm programming a simulation of a projectile that has a known target off in the distance somewhere in my 3D world, i also know the angle at which i will be firing the projectile. i am firing the projectile on flat ground (so the start and end y-coordinates are the same). i'm...

Homework Statement In a baseball game, a batter hits the ball at a height of 4.60 ft above the ground so that its angle of projection is 52.0º to the horizontal. The ball lands on the grandstand, 39.0 ft up from the bottom. The grandstand seats slope upward at 28.0º with the bottom seats 358...

A ball is thrown into the air from ground level. After a time t = 2 s, the ball has traveled to a position x1 = 27 m to the right of and y1 = 10 m up from where it was thrown (at this time, the x and y components of the ball's velocity are still positive). The axes show the x and y directions to...

Homework Statement I'm having trouble finding the initial velocity without knowing the time. A basketball player is standing on the floor 10.0 m from the basket. The height of the basket is H = 3.05 m, and he shoots the ball at an angle, θ = 42.0°, with the horizontal from a height of h =...

Homework Statement A ball with mass m = 1.72 kg is attached to a peg at the origin using a length of massless string of L = 1.54 m. It is released from the top of a vertical circle with speed v0 = 4.81 m/s. What is the ball’s speed (m/s) when the string makes an angle θ = 21.7° above the...

Homework Statement What is the motion of a body thrown upwards from the Earth's surface, with escape velocity as it's initial velocity. Disregard the air resistance. Homework Equations v_e = \sqrt{\frac{2 G M}{x}} F_g = \frac{G M m}{x^2} The Attempt at a Solution I though this...

Hi, I am trying to find the initial velocity of this question: Using a video camera, it is observed that when a ball is kicked from A, it just clears the top of a wall at B as it reaches its maximum height. Knowing the distance from A to the wall is 20m and the wall is 4m high, determine the...

Homework Statement A truck drives in a straight line, east, from point A to point B, a distance of 180 meters, during 10 seconds, while slowing down at a constant rate of 6 meter per second squared. Calculate the initial velocity. The Attempt at a Solution Attached. I don't think...

Homework Statement A deer jumped out at 40 m in front of a car traveling at 30 mph. If the car managed to stop with 10 m to spare. Determine the velocity at which the car would be traveling so that the collision could not be avoided. Homework Equations Vf2=Vi2+2*AD Vf=Vi+At...

?!??Find an initial velocity v such that there's no oscillation,is my solution correct Homework Statement Can somone kindly tell me if my solution to question C and D is correct, if not, what did i do wrong? http://img9.imageshack.us/img9/4914/b52009cd.gif Homework Equations The Attempt at...

Homework Statement a ball that is 10cm in diameter is thrown 2.4m above the level of hands vertically to reach a ceiling what is the initial velocity Homework Equations struggling to determine the intial velocity as have no time The Attempt at a Solution Help! really struggling

Homework Statement a block is at the base of a ramp of angle 35degrees. The ramp is 5 m long and has a coefficient of static and kinetic friction of .6 and .2 respectively. The block is initially given a velocity of 12 m/s up the ramp, how far from the ramp will the block land? my main...

Homework Statement A baseball is hit at a 45 degree angle 1.3m above the ground. It barely clears a 3m wall 130m away. With what velocity was the ball hit? Homework Equations Equations of Motion The Attempt at a Solution So I realized that without air resistance this would be a...

Good Afternoon, wondering if I could get some assistance. I'm not formally learning physics its just an interest I have, and try to complete problems during my spare time. I have one particuar question that I'm stumped with, so any help would be great! Q: You are asked by a film director...

Homework Statement Coyote falling down with a parachute holding an anvil at 10m/s. At 50m he drops the anvil. A) How long does it take for the anvil to hit the ground? B) what is the velocity of the anvil right before it hits the ground? Homework Equations X= Xo + V0T+1/2A(T^2) g= 9.8...

Homework Statement In a circus act, clowns are shot from a cannon at a constant speed vo = 11.1 m/s. The angle of launch may be varied. What is the maximum distance D that a clown may travel, if the landing pad is at the same height as the mouth of the cannon? Knowns: Vo=11.1 m/s x = 0 y...

Homework Statement A 3.55 kg object sliding on a frictionless surface breaks into two masses that are both equal to half of the original mass. The velocities of the masses are 3.26 m/s due north and 4.58 m/s, 25.4° north of east. Determine the original speed of the 3.55 kg mass. Homework...