Motion Definition and 999 Threads

Homework Statement This question is referring to the classic ball in a loop question where it is dropped from a height and slides into a loop de loop. Derive an expression in terms of theta the velocity of the ball at the time it loses contact with the track. Theta is measured from the...

1. Homework Statement In picture Homework Equations f=ma v^2/r The Attempt at a Solution ΣFy=-mg - Fn = m(-v^2/r) -55*9.8 - Fn = m(-v^2/r) v= 16π/4.5 since circumference = 2πr divide by the rotations time taken per second = 11.17m/s -Fn = 55(-15.6) + 55*9.8 Fn = -319 What am i doing wrong here??

Greg Bernhardt submitted a new PF Insights post Rindler Motion in Special Relativity, Part 2: Rindler Coordinates Continue reading the Original PF Insights Post.

I am writing a lab report on the effect of the radius of a string on the frequency of rotation on an object in horizontal uniform circular motion. My hypothesis is: If the radius of the string from the origin of rotation increases, then the frequency will decrease because frequency has an...

Homework Statement Viewers of Star Trek have heard of an antimatter drive on the Starship Enterprise. One possibility for such a futuristic energy source is to store antimatter charged particles in a vacuum chamber, circulating in a magnetic field, and then extract them as needed. Antimatter...

Hello Consider a pulley with a rope winded up around it, and two solids attached to the rope from each side. It is intuitive that the solid with the most mass will impose the direction of the rotational motion of the system ( note that the pulley can rotate), but i'd like to know how can we...

Homework Statement A model yacht runs on a horizontal frictionless oval track as shown (viewed from above) in the figure. The curved parts of the track are semi-circles of radius ##R = 0.5 m##; the straight sides have length ##L = 1 m##. The mass of the yacht is ##m = 0.5 kg.## A force of...

Two stationary masses will attract each other. That is, they start moving towards each other. For example, a stationary apple will fall to earth. I can see bent space affecting the trajectory of a moving object. ...but how does bent space explain that stationary objects start moving?

I'm reading the first Feynman volume on physics. In the chapter about Conservation of Energy, the author explains with the following sentence what is a perpetual machine ( in this case a weight-lifting machine). "If, when we have lifted and lowered a lot of weights and restored the machine to...

I need help calculating travel time as a function of distance using drag equation: F_drag = crossection area * density * ballistic coefficient * 0.5 * v^2. Not posted in homework cause it's not, and I don't know how to solve integrals so I could not fill solution attempt box

Homework Statement In a practical that we conducted, we were investigating the relationship between Launch height and the range (horizontal distance it travels) of a projectile. We launched a projectile from various heights and measured the horizontal range it traveled before reaching the...

Homework Statement This isn't really a homework problem/question. I am just wondering if it is possible to calculate the vertical distance (dy) when the only given values are those of the horizontal distance (dx) and velocity (v). An example of this projectile-motion problem would be this: A...

Greg Bernhardt submitted a new PF Insights post Rindler Motion in Special Relativity: Hyperbolic Trajectories Continue reading the Original PF Insights Post.

Homework Statement A particle moves in a straight line with the acceleration shown in the figure. Knowing that it starts from the origin with ##v_0 = -14ft/s##, plot the v-t and x-t curves for 0 < t < 15 s and determine (a) the maximum value of the velocity of the particle, (b) the maximum...

Homework Statement Homework Equations T = 2pi * sqrt(m/k) mv =m2v2 (LM)[/B]The Attempt at a Solution [/B] So T2 depends on the mass and not velocity. So i can find T2 = 2pi * sqrt([m/2]/k) For A2 , i know that the amplitude before any collision is 1/2m1v1^2 = 1/2kA1^2 so solving that, i...

Homework Statement 11.9 The brakes of a car are applied, causing it to slow down at a rate of ##10 ft/s^2##. Knowing that the car stops in 300 ft, determine (a) how fast the car was traveling immediately before the brakes were applied, (b) the time required for the car to stop Homework...

Homework Statement 11.10 The acceleration of a particle is directly proposional to the time t. At t = 0, the velocity of the particle is v = 16 in./s. Knowing that v = 15 in./s and that x = 20 in. when t = 1 s, determine the velocity, the position, and the total distance traveled when t = 7s...

Homework Statement 11.8 The motion of a particle is defined by the relation ##x=t^3 - 6t^2 - 36t - 40, where x and t are expressed in feet and seconds, respectively. Determine (a) when the velocity is zero, (b) the velocity, the acceleration, and the total distance traveled when x = 0...

Hi, The article below states that they made a material that blocks the motion of molecules in only one way but passing the other way is possible. See the article. https://physicsworld.com/a/blocking-the-symmetry-of-motion/ This seems to me in contrast with the second law. You can for example...

Homework Statement 11.7 The motion of a particle is defined by the relation ##x = 2t^3 - 15t^2 + 24t + 4 where x is expressedin meters and t in seconds. Determine (a) when the velocity zero , (b) the position and the total distance traveled when the acceleration is zero Homework EquationsThe...

Homework Statement The motion of a particle is defined by the relation ##x = 6t^4 - 2t^3 - 12t^2 + 3t + 3##, where x and t are expressed in meters and seconds, respectively. Detrmine the time, the position, and the velocity when a = 0. Homework EquationsThe Attempt at a Solution [/B] Can...

Homework Statement Given a cylinder is rolling purely and a man with mass m is attatched to a point in the circumference of the cylinder. As the man approaches the lowest point he jumps vertically up. Will the velocity of the cylinder increase, decrease or remain same after the man is detached...

Homework Statement Find the velocity ± and the position x as functions of the time t for a particle of mass m, which starts from rest at x =0 and t =0, subject to the following force functions: (a) Fx = F0 + Ct (b) Fx = F0 sin Ct Ct (c) Fx = F0e^ct where F0 and c are positive constants...

Homework Statement A thin rod of length ' L' lies on the + x-axis with it's left-end at the origin. A string pulls on the rod with a force 'F' directed towards a point 'P' a distance 'h' above the rod. Where along the rod should you attach the string to get the greatest Torque about the...

Let's consider a particle moving along x – axis, its position at t = 1s is 1m and speed is 1 m/s. How can one calculate acceleration on the basis of this information?

Homework Statement Homework Equations V^2=rgtan The Attempt at a Solution V^2=.24x9.8xtan25

Let's suppose we have a body A with mass M that can move on a horizontal frictionless ground. Now we connect that with another body B, mass m, with the help of a rope. The body B can move vertically and the rope is curved with a pulley. Now we set the body B free to move. What's the relationship...

Homework Statement Nikhil is probably eating his daily snack at this time. Old Man Miller comes back from the store and takes the 0.150kg sandwich from Nikhil as he begins to run away. Nikhil is running at 7.5m/s away from me when I hit him in the head with the sandwich that was moving at...

Homework Statement So I've been stuck on this exercise for a few hours now, maybe you can help out: 3 balls meet at the same height hm. Ball 1 is accelerated straight up into the air for 1s from height 0. When the acceleration stops, ball 2 is launched straight up from height 0 with v2 =...

Homework Statement Mariana is volleying with Old Man Miller and returns one of his feeble tennis serves. He serves the ball such that it is moving at a speed of 35km/h [Forward] when she strikes the 0.060kg ball and sends it back over the net at a velocity of 55km/h[Backward]. a) If the ball...

1. the question is this: a projectile's speed at launch is four times its speed at the top of the trajectory. What is the launch angle? I am given no numerical values, but from my understanding gravity is a constant 9.8, and at the maximum height velocity should be equal to 0. 2.the equation...

https://www.physicsforums.com/attachments/221718 Say if we have two particles P, and Q, traveling at velocities Vp and Vq respectively. If it is IMPOSSIBLE for Q to collide with P, let us find the distance of closest approach. So from the frame of reference of P, itself is stationary, and Q is...

Homework Statement What is the distance from the Earth's center to a point outside the Earth where the gravitational acceleration duo to Earth is 1/10 of its value at the Earth's surface? Homework Equations F = Gm1m2/r2 F = m1 (v2/r) Mass of Earth = 5.98x1024 G = 6.67x10-11 The Attempt at a...

Homework Statement In picture attatched Homework Equations acceleration centripetal, acceleration perpendicular, velocity The Attempt at a Solution I found that i can project the acceleration onto the velocity and get theta = -135 degrees between acceleration and velocity vector. so the...

Homework Statement When if ever is the speed of the object increasing? Homework Equations Dot product result, cos(theta) acceleration perpendicular, acceleration parralel The Attempt at a Solution I solved the problems first three parts and found when the objects speed is constant using the...

1. Homework Statement I'm doing lab, and to start we have to find ΔX of a projectile launched an angle. The first step for us is to find time, and to make it easier our teacher recommended us to first set the angle to zero, and find time like that. I don't have enough X information to find...

Homework Statement Reading chapter 4 of Morin's "Introduction to classical mechanics" I came across to the explanation of the damped harmonic motion. The mass m is subject to a drag force proportional to its velocity, ##F_f = -bv ##. He says that the total force of the mass is ##F= -b \dot{x}...

Homework Statement In my robotics class I was task with creating a robot to lift and house objects, I have the lifting mechanism, and a housing area, but I can't figure how to get the bucket of the robot to dump using a rotary motor. Homework EquationsThe Attempt at a Solution Tried to fixate...

Homework Statement In microgravity astronaut training and equipment testing, NASA flies an aircraft along a parabolic flight path. The aircraft climbs from 24,000 ft to 31,000 ft, where it enters a parabolic path with a velocity of 143 m/s nose high at 45.0° and exits with velocity 143 m/s at...

Homework Statement Homework EquationsThe Attempt at a Solution I am not quite understanding what is given in the question .Are the two directions of the fields known to us ? Assuming we know the two directions , say for example if we know that the two fields are in x and y directions , but...

Homework Statement Problem Statement: A system consists of a long cylindrical anode of radius a and a coaxial cylindrical cathode of radius b (b < a). A filament located along the axis of the system carries a heating current I producing a magnetic field in the surrounding space. Find the least...

Hello, I am a new member looking for the answer to a question I recently had on an exam. I will not know if I got it right for up to 6 weeks so am curious. Question is: A faucet drips water at 5 drops per second. calculate the distance in metres between the first and second drop after the first...

I'm creating a tennis game and at this point I'm trying to model ball motion. I found multiple lectures on projectiles equations of motion which seem to apply well for when ball is not moving, but they do not take into account the velocity may have at the time of impact. For example, I found a...

Hello Everybody! My name is TanX and I got a figure in my mind while studting concepts related to Vertical Circular Motion. I tried finding a solution to it (i.e) I tried finding the condition for movement of the particle in the figure that had come in my mind... Homework Statement So here is...

Homework Statement 1.[/B] two balls are thrown vertically from two points on a building. at the bottom of the building ball 1 is thrown and from the roof ball 2 is thrown. ball one reaches its maximum height after three seconds and ball two after one second. after two seconds the balls cross...

Homework Statement Answer: Can someone explain the answer? I don't understand why it's necessary for that the moment when the force exerted on the smaller block is greatest is when it is on the verge of slipping. Could it not already have been slipped off or maybe even 3/4 way slipped off...

A ball is shot from the ground into the air. At a height of 9.1 m, its velocity vector (in unit vector notation) is (7.6i - 4.9j) m/s; that is, vx = 7.6 m/s and vy = -4.9 m/s. What was the maximum height of of the ball above the ground? I swear to god i have been working on this for 2 hours...

Homework Statement A ball was thrown from a cliff, it reached to the ground after 2.5 seconds. a) Find the height of the cliff. b) Find the horizontal distance the ball reached. Homework Equations Δy = 2⋅g⋅t^2 Vfy = g⋅t √(Vfy)^2+(Vfx)^2 Δx= Vx⋅t The Attempt at a Solution I've found Δy=30.6m...

Homework Statement If a river is going 6 km/hr relative to the ground, a boat is going 14 km/hr relative to the river, and a man is jumping from one end of the boat to the other at 6 km/hr relative to the river. What is the speed of the man relative to the ground? I'm stuck between the...

I and my teacher argued whether a uniform circular motion in polar coordinates is considered to be a motion in one dimension or it's a motion in two dimensions.