Kinematics Definition and 1000 Threads

  1. J

    Maximum and minimum speeds in a moving cube

    Homework Statement A rigid cube in the figure moves in space. At a certain time ##t## its front face ##ABCD## is vertical and the velocity of vertex ##A## is vertical down ##v## while the velocity of its vertex ##D## makes an angle with the vertical and has magnitude ##v_{2}## while lying on...
  2. J

    Acceleration of a particle on a parabola

    Homework Statement A particle moves along a parabola on the x-y plane with equation ##y^{2}=2px## with constant speed ##1000m/s##.What is the magnitude of its acceleration? Homework Equations Parametric equations ##\vec{r}=(b^{2}t^{2}/(2p),bt)##. The Attempt at a Solution...
  3. W

    MHB Kinematics Application Question - Physics 11u

    In a 100 meter race, Maggie and Judy cross the finish line in a dead heat, both taking 10.2 seconds. Accelerating uniformly Maggie took 2.00 seconds and Judy 3.00 seconds to attain maximum speed, which they maintained for the rest of the race. a)What was the acceleration of each sprinter...
  4. J

    How Late Did the Man Arrive to Catch the Train?

    Homework Statement A man arrives ##T## seconds late to a train station. He watches the last three cars of the train pass by. The next-to-the-next-to-last car takes time ##t## to pass by the passenger, the next-to-last car takes time ##t'## to pass by and the last car takes time ##t''## to...
  5. C

    What is the net acceleration of the coin on a rotating disk?

    Homework Statement A disk is initially at rest. A penny is placed on it at a distance of 1.4 m from the rotation axis. At time t=0s, the disk begins to rotate with a constant angular acceleration of 1.9 rad/s^2 around a fixed, vertical axis through it's center and perpendicular to it's plane...
  6. L

    I get two different answers when solving a kinematics problem

    1. A car accelerates for 200 meters and has an initial velocity of 2.0 m/s and a final velocity of 6 m/s. What is the acceleration of the car if this change in velocity takes 12 seconds?Homework Equations a=Δv/Δt Δx=Vi*t+.5at2[/B]The Attempt at a Solution When I solve this using the first...
  7. E

    Kinematics: find the particle's position as a function of time

    Homework Statement There is a particle that moves in 1-dimension. mass is m, force on the object is given as a function of position(x), Fx= -mω2x.(ω is constant) when t=0 particle has x0>0, and velocity is zero. find the particle's position as a function of time. Homework Equations There is a...
  8. AntSC

    Modifying Newton's Kinematic Equations for High Altitude

    I recently watched a video on youtube where a guy fires a 50 cal. rifle straight up into the air and measures the time of flight at about 100s. It got me thinking about what altitude the round reached. So I used the kinematics equations and obtained a value of 12.25km. Amazing, but I wondered...
  9. solarmidnightrose

    B Understanding Kinematics in Calculus for High School Students

    hi, I'm a high-school student that is just beginning to learn calculus. in calculus we are learning how to apply integration and diffrentiaiton methods regarding kinematics. there is this certain phrase i do not really understand in our textbook: e.g."in the second second" how am i meant to...
  10. devilish_wit

    I have a hard time with kinematics involving inclined planes

    Homework Statement Two blocks of mass m1 = 3.00 kg and m2 = 6.00 kg are connected by a massless string that passes over a frictionless pulley (see the figure below). The inclines are frictionless. Image - https://www.webassign.net/serpse9/5-p-049.gif The inclined plane is shaped like a...
  11. V

    Complex Kinematics and Dynamics

    Homework Statement Two pucks (5 kg each) made of Teflon are on a long table, also made of Teflon. Puck A is sitting at rest on the left end of the table. Puck B is 15 m away at the right hand end of the table, and is travelling toward Puck A with an initial speed of 0.5 m/s. A person on the...
  12. V

    Complex Kinematics and Dynamics

    Homework Statement Two pucks (5 kg each) made of Teflon are on a long table, also made of Teflon. Puck A is sitting at rest on the left end of the table. Puck B is 15 m away at the right hand end of the table, and is travelling toward Puck A with an initial speed of 0.5 m/s. A person on the...
  13. L

    Was the Driver Speeding Before the Crash?

    Homework Statement "Based on the following data, determine if the driver who crashed was driving over the speed limit" The relevant data given is: -A 2002 Volvo t-bones a truck in an alley with a speed limit of 20km/h -An eyewitness heard tires screech, then a loud bang, and also said the...
  14. M

    How do we find the uncertainty of v in the kinematics eqn?

    Homework Statement Given the kinematics equation v2 = u2 + 2as, find the uncertainty Δv. Given: Values of a, s, u, and their associated uncertainties. Homework Equations v2 = u2 + 2as The Attempt at a Solution I'm aware of the rules for uncertainty propagation, but what do I do in this case...
  15. alexi_b

    Finding when acceleration is zero

    Homework Statement A block of mass 2.42kg is accelerated across a rough surface by a rope passing over a pulley, as shown in the figure below. The tension in the rope is 13.9N, and the pulley is 12.3cm above the top of the block. The coefficient of kinetic friction is 0.395. A: 2.28 m/s^2...
  16. alexi_b

    How far apart are the astronaut and satellite after 8.67 minutes?

    Homework Statement A 63.8kg spacewalking astronaut pushes off a 678.0kg satellite, exerting a 156.0N force for the 0.870s it takes him to straighten his arms. How far apart are the astronaut and the satellite after 8.67min? Homework EquationsThe Attempt at a Solution I tried just finding the...
  17. P

    How do you find the acceleration needed to clear a jump?

    Homework Statement Homework Equations The Attempt at a Solution I used Pythagorean theorem to find the length of the ramp (25^2+18^2 = √949) and found the angle of elevation using tangent (Tanθ=18/25) but then got stuck on what formula to use.
  18. K

    Kinematics within a simulation

    Homework Statement I'm simulating a warehouse (in Unity) where forklifts and other vehicles transport stuff from point A to point B. The routes are modeled as a graph with vertices and edges. Every transport is saved as a task in a backend system with the relevant data such as starting time...
  19. S

    What is the total torque of that system?

    Homework Statement A load was put on the right side of a seesaw 0.6 meter from its center as shown, on the other side a force of 49N is applied perpendicular to the seesaw surface 1 meter from its center, the setup is tuned to an angle of 30 from the horizontal axis as shown. On the right...
  20. Z

    Kinematics Problem: Train braking and blocking an intersection

    Homework Statement A train 400 m long is moving on a straight track with a speed of 21.6m/s. The engineer applies the brakes at a crossing, and later the last car passes the crossing with a speed of 5.0m/s. Assuming constant acceleration, determine how long the train blocked the crossing...
  21. Abhimessi10

    Charge entering into the field between capacitor plates

    Homework Statement A negative charge of mass m enters into the field between two deflecting parallel plates with length 'l' separated by distance 'd' with a velocity 'v'.Assuming electric field to be uniform,find the maximum charge so that it will not hit a plate Homework Equations Kinematic...
  22. J

    How Do You Calculate the Meeting Point of Two Stones Thrown from a Cliff?

    Homework Statement Two stones are thrown simultaneously, one straight upward from the base of a cliff and the other straight downward from the top of the cliff. The height of the cliff is 6.00m. The stones are thrown with the same speed of 9.0m/s. Find the location (above the base of the cliff)...
  23. L

    Kinematics: find maximum height

    Homework Statement A rocket takes off from the launch pad and moves directly upward with an acceleration of 29.4 m/s2. It runs out of fuel after 4s and continues to coast upward, reaching a maximum height before falling back down to Earth. a) Find the rocket's maximum height. b) What is the...
  24. gibberingmouther

    Understanding the 1-D Kinematics Equations

    So, the equations I'm talking about are the "big 4" listed here: https://www.physicsclassroom.com/class/1DKin/Lesson-6/Kinematic-Equations I understand how to derive all these using calculus or algebra and graphs. That's not my problem. I can apply them pretty well to problems I need to...
  25. M

    Kinematics: baseball toss with an angle provided

    Homework Statement An outfielder throws a baseball to his catcher in an attempt to throw out a runner at home plate. The ball bounces once before reaching the catcher. Assume the angle at which the bounced ball leaves the ground is the same as the angle at which the outfielder threw it as shown...
  26. DracoMalfoy

    Projectile Motion Kinematics: A catapult launches a rock....

    Homework Statement A catapult launches a rock with an initial velocity of 50m/s at 35 degrees above the horizontal. The rock must clear 3.5m at 10m away in order to make it over a castle wall to get to the enemy. Do the knights succeed? By how much do they clear the wall or miss clearing the...
  27. DracoMalfoy

    Kinematics: Ball thrown off of a building

    Homework Statement A ball is thrown off of a building in the +x direction at 10m/s. If the ball takes 2s to land, how tall is the building? Homework Equations Vf=Vi(a)(t) Δd=Vi(t)+1/2(a)(t) Vf^2=Vi^2+2(a)(Δd) Δd=1/2(Vf-Vi)(t) The Attempt at a Solution Vf: 0m/s Vi: 10m/s a: -9.8m/s^2 t: 2s...
  28. DracoMalfoy

    Projectile Motion Kinematics: Finding maximum height

    Homework Statement A ball is kicked with an initial speed of 20m/s at an angle of 50° above the horizontal. What maximum height does the ball reach? Homework Equations Vfx=VicosΘ Δx=VicosΘt Vfy=(VisinΘ)+ay⋅t (Vfy)^2=(VisinΘ)^2+2ay⋅Δy Δy=1/2(Vfy+(VisinΘ))⋅t The Attempt at a Solution I...
  29. DracoMalfoy

    Kinematics: Motion in One Direction: Car Chase

    Homework Statement A car traveling at a constant speed of 24.0m/s passes a trooper hidden behind a billboard. One second after the speeding car passes the billboard, the trooper sets off in a chase with a constant acceleration of 3.0m/s^2. A) How long does it take the trooper to overtake the...
  30. baldbrain

    'They' haven't considered centripetal acceleration

    Homework Statement A train is moving counter-clockwise with a constant speed of 10 m/s in a circle of radius ##\frac {16} π## m. The plane of the circle lies in the x-y plane. At time t = 0, the train is at P, when a stone is thrown from it with a speed of 10 m/s relative to the train towards...
  31. DracoMalfoy

    Kinematics: Two engines, One Rocket, and Displacement.

    Homework Statement A Rocket with an engine that causes a net acceleration of 4m/s^2 launches with an initial velocity of 20m/s. The engine fuel lasts for 0.8s. A secondary engine then fires causing a net acceleration of 2m/s^2 for 0.6s How far off the ground is the rocket when the secondary...
  32. DracoMalfoy

    Trouble with another Kinematics question

    Homework Statement A person riding a bike travels at an average velocity of 3m/s for 30min. The person then takes a water break for 15 min. The person finally travels a distance of 450m at an average velocity of 1.5m/s. What is the persons average velocity? 2. Homework Equations [/B] Average...
  33. john-b

    Inconsistency in a Velocity-Time Graph

    Homework Statement We're supposed to convert a position-time graph to a velocity-time graph to an acceleration time graph. These are the values for the position-time graph: Homework Equations m = y2-y1/x2-x1 The Attempt at a Solution I found the slopes for each time which were 5, 8.5, 17...
  34. DracoMalfoy

    Calculating Acceleration for a Car Stopping on a Dime: Kinematics Question Help

    Homework Statement A commercial claims that a car can stop on a dime (17.9mm). If a car is initially traveling at 13.4m/s, what acceleration would the car experience coming to a stop in that short distance? Homework Equations avg acceleration Coversion The Attempt at a Solution I recognize...
  35. DracoMalfoy

    Average Acceleration Calculation for Ball Bouncing off a Tennis Racket

    Homework Statement A ball is traveling at 3m/s then bounces off of a tennis racket and returns at 2m/s. If the ball is in contact with the racket for 12ms, what is the average acceleration? Homework Equations average acceleration and conversion a=Vf-Vi/Tf-Ti 1s= 1000ms The Attempt at a...
  36. DracoMalfoy

    Kinematics Equations: Displacement Calculation with a Wheel | Homework Help"

    Homework Statement A straight line is marked in meters in a field. A student begins at the zero position mark and ends at the 50 position mark. However, the student did not walk along the straight line. He uses a wheel that has a circumference of 1m and finds that it turns 100 times as he...
  37. DracoMalfoy

    Need help with this question regarding kinematics.

    Homework Statement a) A ball is thrown in the -y direction off of a cliff with a velocity of 7m/s. If the ball takes 1.45s to reach the ground, how high off of the ground is the cliff? (Answer: -20m) Homework Equations Vf=Vi+a(t) Displacement=Vi(t)+1/2a(t)^2 Vf^2=Vi^2+2a(Displacement)...
  38. C

    Equivalence of tipping conditions on an inclined plane

    We have a cube on an inclined plane. The tipping condition is the presence of an unbalanced torque relative to the center of mass (contributing forces are: the normal force and the force of friction). However, is this conditions equivalent to the previous one: The line of action of the force of...
  39. baldbrain

    Reaction time while stopping a car

    Homework Statement To stop a car, first you require a certain reaction time to begin braking; then the car slows down under constant breaking decelaration. Suppose that the total distance moved by the car during these two phases is 56.7 m when its initial speed was 80.5 km/h and 24.4 m when its...
  40. C

    Air resistance - freefall and horizontal projectile motion

    We have two identical balls sitting at the same height. One of them is released without applying any force (it falls freely) and the other one is given a non-zero horizontal velocity. Which of them will hit the ground first? The force of air resistance is proportional to the square of the...
  41. C

    I Spinning bicycle wheel in air and letting it go

    Let's say that we have a bicycle wheel with radius $R = 25 cm$ and mass $m = 1 kg$. We spin the wheel in air so, that the tread is moving at the speed of $v_o = 50 km / h$. Then, we let it roll on asphalt, given the coefficient of static friction: $f_s = 0.9$ and kinetic friction: $f_k = 0.7$...
  42. baldbrain

    River-boat problem (Relative velocity)

    Homework Statement A man wishes to cross a river of width 120 m by a motorboat. His rowing speed in still water (or relative to water) is 3 m/s and his maximum walking speed is 1 m/s. The river flows with a velocity of 4 m/s. (a) Find the path which he should take to reach the point directly...
  43. enter

    Negative Velocity or Acceleration

    So, velocity is a vector, right? And vectors can't have negative magnitudes, right? Then why is leftward velocity considered negative in 1D kinematics? It just seems off to me. Same with acceleration, and pretty much _every vector in all of physics._
  44. Liszzy

    Physic (kinematics) — Displacement of an accelerating car

    Question: A car accelerates from rest at a rate of 2.0m/s^2 [N]. What is the displacement of the car at t=15s? I tried (2m/s^2 [N])(15s)=30m/s [N] (30m/s [N])(15s) =450m [N] but guess wrong :( *Because the answer is 230m [N] How to solve this? anyone
  45. prakhargupta3301

    Where Is the Error in Calculating the Distance Traveled?

    Homework Statement Only (b) part[/B] Homework Equations time of flight= (2⋅u⋅sinθ)/g ---------------- - 1 total distance (range)= u⋅cosθ * time of flight (s=vt) =u⋅cosθ * (2⋅u⋅sinθ)/g...
  46. Alexanddros81

    Determine the ground speed and the course of the plane

    Homework Statement 15.1 The airspeed of the plane is 200m/s, directed north. If the wind speed is 30m/s in the direction shown, determine the ground speed and the course (angle θ) of the plane. Homework Equations The Attempt at a Solution Is it so far correct the above? More questions...
  47. prakhargupta3301

    Exploring the Relationship Between Velocity and Displacement in Pulley Systems

    Homework Statement Homework Equations xcxcxcxcxcxcxcxcxcxcxc[/B]The Attempt at a Solution My attempt: Let displacement of A be x m, Let displacement of B be y m, and Let displacement of C be z m. Step2: [/B]a+b+c+d=(a+x-y)+(b+x)+c+(d+z) 2x-y=-z Differentiating LHS and RHS components...
  48. prakhargupta3301

    Having a problem in steps while solving integrals

    Homework Statement My problem is in integral calculus (I'm new to it). I know what it is and how it works (basically. I'm not too advanced right now). The problem is as following: (I will be posting comments/reasons along with what I've done and with what logic/understanding I've done it...
  49. T

    Kinematics derivation: what's "ds/dv" ?

    Hello, here's a derivation for one of the equations for Uniform Accelerated Motion (UAM). I like it because it's far more concise than the algebra version. Question though: is there any kind of meaningful interpretation of ds/dv (which starts everything off in step 1)? Thank you!
  50. David Laeni

    Gradient of acceleration-time graph- Kinematics.

    What does the slope/gradient of an acceleration-time graph indicate?
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