Kinematics Definition and 1000 Threads

Homework Statement Marian, who is standing on her balcony, is surprised by a pigeon and throws a flowerpot up in the air at 2.1 m/s. It takes 3.0 s for the flowerpot to smash to the ground. The flowerpot experiences acceleration due to gravity of 9.81 m/s2 [down]. Determine how high Marian's...

Homework Statement http://imgur.com/0t8TVgq http://imgur.com/0t8TVgq [Image copy inserted by moderator] Sorry about all the erase marks. My question is why is the final velocity not 0. Homework Equations V=Vo+at[/B] The Attempt at a Solution So the question is asking for the horizontal...

Homework Statement http://pho.to/A7jM2 Homework EquationsThe Attempt at a Solution My question is why the answer of question 15.258 (a) about the angular acceleration of rod BD isn't correct. I used the realtion of tan(25) in the end of the solution.

Homework Statement Hey guys, I have a question about this(I know you want to see my soultion, but I've done it ok except the 2 things I'm asking about) : http://athena.ecs.csus.edu/~grandajj/me143/1_Introduction_Tires_WM2D/1_4_2_Exercise_2.pdf 2 questions: 1. How can I undersdant that I...

My question is what inverse kinematics is. Many scientists are using inverse kinematics for measuring cross-section or something. For example, suppose that we measure cross section of 14N+p->n+14O. We can use N14 for beam and p for target. But, we can also do the other way. When they use...

[Note: Post moved to homework forum by mentor] So I stumbled upon a reviewer for my physics exam tomorrow and I was wondering how the equation was formulated. Your help is very much appreciated :) ! Normally I would consult my professor for this but it's Sunday in my country today so I can't...

Does anyone know of any good books on kinematics? Preferably not extremely advanced, thanks!

Homework Statement This is a physics olympiad problem; and I am still struggling with it. I will quote it here: " A particle moves along a horizontal track following the trajectory $$r=r_{0}e^{-k\theta}$$, where $$\theta$$ is the angle made by the position vector with the horizontal. Recall...

Homework Statement A charged particle (either an electron or a proton) is moving rightward between two parallel charged plates separated by distance d=2.87mm. The plate potentials are V1=-75.8V and V2=-49V. The particle is slowing from an initial speed of 90.0 km/s at the left plate. What is...

So, my thread title was too long, here is the full title: Why should the kinematics equations be taught in a regular high school physics course? < Mentor Note -- thread title fixed (we can lengthen titles) >[/color] Let me explain my situation. I will teach physics in a different country...

So, my teacher is going to do almost like an interview to the class, asking our knowledge about Dynamics and Kinematics, and I was wondering if I can get questions to test my knowledge in Dynamics and Kinematics to get ready for it.

Homework Statement A passenger train is traveling at 27 m/s when the engineer sees a freight train 345 m ahead of his train traveling in the same direction on the same track. The freight train is moving at a speed of 5.9 m/s. (a) If the reaction time of the engineer is 0.36 s, what is the...

Homework Statement An object is thrown with velocity v from the edge of a cliff above level ground. Neglect air resistance. In order for he object to travel a maximum horizontal distance from the cliff before hitting the ground, the throw should be at an angle theta with respect to the...

Homework Statement Open image in new tab to enlarge please :) Homework Equations I was trying to compare the initial KE/PE with the final KE/PE in order to find out how far the skateboarder rose but the solution was wrong for some reason? Keep in mind the skateboarder is traveling along the...

When we apply this equation ? v^2-u^2=kt^2/2m

Homework Statement so I am sending my unit in for marking, and i collected a bunch of kinematic related questions that I've attempted to answer, but don't know if I am on the right track. Any help would be appreciated. Thanks. 1.[/B] 2. 3. 4. 5. Homework Equations relevant equations...

Homework Statement I'm really having a hard time with this question, i posted the same question on another forum, but didn't really understand what the teacher was trying to say, please explain for me. thank you :) a) Calculate the time per mode of transport of the lettuce from each starting...

Homework Statement Homework Equations average speed = total distance/total time The Attempt at a Solution 24. [/B] The shortest road distance from Toronto City Hall to the Shaw festival theatre in Niagara-on-the-Lake is 131 km. a) First I will calculate the area of each rectangle using...

Homework Statement Homework Equations average speed = total distance/total time average velocity = total displacement/total time The Attempt at a Solution please verify if my answers are correct. Thanks :D im specifically having doubts about a), i don't know how to identify when the truck...

Homework Statement Homework Equations acceleration equation: a = v2 – v1 / t2 – t1 The Attempt at a Solution Can someone please tell me if my answers make sense. Thanks in advance :)[/B] 21. 22. to calculate the velocity, i determined the slope of the tangents, postioned at 0.50s...

Homework Statement A 50m zipline is hung 11m off of the ground at its starting point (assume it ends at ground level). If you are to drop an object which is 20m along the ground from the start of the zipline, how far down the line would you need to let it go? Homework Equations d=((VF+VI)/2)*t...

Homework Statement Two canoeists, A and B, live on opposite shores of a 300.0 m wide river that flows east at 0.80 m/s. A lives on the north shore and B lives on the south shore. They both set out to visit a mutual friend X who lives on the north shore at a point 200.0 m upstream from A and...

Homework Statement a) Calculate the time per mode of transport of the lettuce from each starting point. b) calculate the total time required for each complete journey of the lettuce from its origin to Barrie c) d) e) Homework Equations time = distance / speed or t = d/v The Attempt...

Homework Statement A plane went 300m/s 35° south of west then 230m/s 20° east of north. What is the magnitude and direction of the 65kg pilot during the 12s turn? Homework Equations Kinematics. Vf = Vi + at, d = ViT + 0.5at^2, Vf^2 = Vi^2 + 2ad The Attempt at a Solution This was a question...

Homework Statement A block of mass m = 2.00 kg is released from rest at h = 0.300 m above the surface of a table, at the top of a θ = 50.0° incline as shown in the figure below. The frictionless incline is fixed on a table of height H = 2.00 m. a. Find a on the incline a=7.51 :) b. Find V(f)...

Homework Statement Two football players separated by 42m run directly toward each other. Football player 1 starts from rest and accelerates at 2.4m/s^2, and football player 2 moves uniformly at 5.4m/s. a) How long does it take for the two players to collide? b) how far does each player move? c)...

Homework Statement Homework Equations y = y0 + Vot + 1/2gt² The Attempt at a Solution We have to know when yball = y rock for the ball : t = t-1 because it's throwed 1 sec later the rock. we have to fine when yball = yrock : 12.t - 0.5*9.8*t² = 18*(t-1) - 0.5*9.81*(t-1)²..I find the answer...

Homework Statement I'm just confused about this. I know that displacement=df-di, but using that formula didn't give me the correct displacement in this case. In a 100m sprint, a runner starts from rest and accellerates to 9.6m/s[W] in 4.2 seconds. The runner runs at a constant velocity for...

Homework Statement If an object is slowing down, does the acceleration automatically have an acceleration of the opposite direction as the initial velocity, even if the question says otherwise? Ex. This is a problem from my textbook: A bus is moving at 22m/s[E] for 12s. Then, the bus driver...

Homework Statement Problem: An object of mass m1 elastically collides with an object of mass m2 =(3/2) m1 that is initially at rest. The less massive object has speed v1 and travels at an angle of θ1with its original direction (x-axis) after collision; the more massive object has a speed of v2...

Homework Statement I saw this in a video about solving projectile motion problems and I was confused, I think I may have seen the same thing in my textbook:The question says: A soccer player on a level playing field kicks a soccer ball with a velocity of 9.4 m/s at an angle of 40 degrees above...

Homework Statement An elevator moving downward at 4.00m/s experiences an upward acceleration of 2.00m/s^2 for 1.80seconds. What is its velocity at the end of the acceleration and how far has it travelled? downward acceleration=-9.8m/s^2, upward acceleration=2.00m/s^2. time=1.80seconds. Initial...

Homework Statement Given the equations X=X0+v0t+1/2at^2 and v=v0t+at, show that an expression for v that has no explicit dependence on time can be written as v=+-√v0^2+2a(X-X0) Homework EquationsThe Attempt at a Solution I thought I would manipulate the first given equation to be X-X0/t =...

Person A travels 10.2m/s[forward]. Person B travels 10.4m/s[forward]. Person C travels 3.51m/s[forward]. Find the average velocity for the trio.I added all 3 velocities(just the magnitudes) and divided by 3, but my answer was different from the textbook's. I got 8.0m/s[forward], but the answer...

so this is just a general question but is it possible to solve all one dimensional motion problems by making graphs, i feel like if that's the case I wouldn't need to use the kinematic equations. I usually get caught up on problems where acceleration changes over time and I have to do...

Homework Statement Anna is driving from Champaign to Indianapolis on I-74. She passes the Prospect Ave. exit at noon and maintains a constant speed of 75 mph for the entire trip. Chuck is driving in the opposite direction. He passes the Brownsburg, IN exit at 12:30pm and maintains a constant...

I am having a lot of difficulty understanding this concept. Suppose you have two objects [FONT=Courier New]A,B[FONT=Courier New] [FONT=Courier New]of mass A',B' [FONT=Arial]connected by a massless rope. Let K Newtons be the force applied on object A .What is now the tension along the rope ...

Homework Statement A stone is thrown from a height 2.1m with an angle of 45 degrees. It fell to the ground 42 m from the throwing position, measured horizontally. Initial velocity is 19,81 m/s, flight time is 3s what is the maximum height? Homework Equations All 2D kinematics equations. The...

Homework Statement A ball is rolling towards a rectangular hole which is 40cm deep and 2cm wide with a velocity 1m/s. It falls through the hole, bounces off the walls a couple of times and falls down. The direction of balls motion is perpendicular to the hole (falling in it from one side)...

I'm having some trouble with this problem (adapted from K&K 1.23). Homework Statement An elevator is programmed to start from rest and accelerate according to \begin{align*} a(t) &= \frac{a_m}{2}\left[1 - \cos\left(\frac{2\pi t}{T}\right)\right] &\mbox{for }0\leq t\leq T \\ a(t) &=...

Homework Statement [/B] During your summer internship for an aerospace company, you are asked to design a small research rocket. The rocket is to be launched from rest from the earth’'s surface and is to reach a maximum height of 990 m above the earth'’s surface. The rocket’'s engines give the...

I'll admit that I'm not an undergraduate(I'm in high school), but I do have a kinematic question that I'm extremely curious about. I basically would like to ask what affects the motion of a projectile, and make it stray from its path. So if I a projectile(let's use a rocket) is flying downward...

a = dv/dt a = (d/dt)(dx/dt) dv/dt = (d/dt)(dx/dt) dv = dx/dt dx = dvdt Xf - Xi = (tf-t0)*dv Is this a valid equation? It doesn't seem right to me since if velocity change is 0, then dv = 0, meaning your change in position is 0. That shouldn't be right, as even though your velocity change is 0...

Homework Statement A motorist drives along a straight road at a constant speed of 14.4m/s. Just as she passes a parked motorcycle police officer, the officer starts to accelerate at 1.8m/s^2 to overtake her. Assuming the officer maintains this acceleration, determine the time it takes the...

Homework Statement A projectile is launched from an origin (0cm,0cm) on a tilted plane. The plane makes 30 degrees with the horizontal. The launcher sends the ball with a speed of 0.2m/s. At what angle should the projectile be launched to hit the target at (0.7m,0.6m) location? Assume there...

Homework Statement An airplane flies horizontally with a speed of 300m/s at an altitude of 300m. Assume the ground is level. At what horizontal distance from a target must the pilot release a bomb as to hit the target? Answer: 2.7km Homework Equations a=v/t=d/t2 r_f = r_i + v_i*t + 1/2at2...

Homework Statement A flowerpot falls off a windowsill and falls past the window below. You may ignore air resistance. It takes the pot 0.420 s to pass from the top to the bottom of this window, which is 1.90 m high. Part A How far is the top of the window below the windowsill from which the...

Homework Statement A body at rest in a frame of reference S disintegrates into two pieces moving in opposite directions. The masses of each fragment are 3.0kg and 4.0kg and their velocities 0.8c and 0.6c, respectively. Find the mass of the body before it disintegrated. (Answer: 10kg) Homework...

Okay, so. I'm doing a project for an environmental geology course in which I need to create a landslide hazard map. Essentially, I have a mass of rock sliding down an inclined plane. I have calculated the kinetic energy and force of the material as it moves down, as well as the final velocity as...

This is a really basic problem but the answers I've gotten don't match up with the back of the book. I've been over it several times & can't understand where I'm going wrong - any pointers would be much appreciated! 1. Homework Statement A physics book slides off a horizontal tabletop with a...