Kinematics Definition and 1000 Threads

TL;DR Summary: Mechanical engineering,robotics,mechnics,dynamics Hi guys , I'm new to mechnics and I want to learn it for building robotic arm , but I find mechanics book topics somewhat difficult for me , what I need to learn to get started as I'm a highschool student with basic level math.

I am confused by the question. So, the first thing I am trying to understand is whether the flag direction will be same to a boat observer as to a ground observer. I know that the flag will orient itself in the direction the wind is blowing towards, so the flag should always point in NE...

My interest is on part (e) only parts a - d were quite easy. I seek an alternative approach for part (e) ...phew this was a nice one ...took me time to figure out. :cool: Find the text solution here: My take/approach; We have ##a=0.6 m/s^2##, therefore; using ##s=ut+\dfrac{1}{2}at^2##, we...

The physical world is highly parallel; many things are happening side by side simultaneously. This is true not only at the macroscopic scales that we can see but as far as we know down to the subatomic scales. This is referred to as the principle of locality [1], which states that an object is...

My reasoning was to use this kinematic equation to first get time of flight of the baseball using horizontal components, and then use this same equation again to find initial velocity.

Can someone guide me how can I find time ?! I don't have any idea. This is a part of a question in Classical Dynamics.

If energy is "not conserved" in General Relativity (or at least, it is difficult to define it) in the context of an expanding accelerating spacetime (like it happens in our Universe), are there any observations of deviations from the strict conservation laws in the evolution and formation of...

I realize that there is a downward force of gravity weighing the object toward earth’s surface, equaling F = mg (downward). The upward force would have to be something at least as much as the downward force in order to lift the object up ”such that it is accelerated from rest to a velocity of 5...

vf=0 km/hr vi = 100 km/hr x = 80,000 km vf2 = vi2+2ax 0 = 100^2 + 2a(80,000) 160,000a = -10000 a = -0.0625 km/hr^2 This is off by 1,000,000 times from the textbook answer. Am I missing something with units or something or is the book wrong?

So far I have this: vbwx= 4.40c0s(28) = 3.88496409 vbwy= 4.40sin28 = 2.065674876 vpwx= 4.4ocos28 vpwy= 4.40sin28 +2.02 Find Square root of vpx^2 + vpy^2 = 5.43? Im confused as to whether we add the 2.02 to the sin28 or the cos28 though, did I do it right? Also, not sure how to find the...

Hi everyone I have solutions to this problem, but I am not sure if the premise behind them is correct. I think this is the reasoning behind the solution for question d. - Work out how far the elevator travels in the 7s before the rock is thrown, so 7x2.5 = 17.5 - Work out how far the...

I'm trying to understand this paper (equation 2.16 specifically): Bini, D., Carini, P., & Jantzen, R. T. (1995). Relative observer kinematics in general relativity. Classical and Quantum Gravity. Am I correct in reading there is no way to express the relativistic relative velocity composition...

Hello there, I have tried the problem but don't get a different of 6g's as I am supposed to. I am not sure whether I interpreted the problem in the correct way, but I would love some feedback/hints on what went wrong in my solution, thanks in advance. Solution: SITUATION DRAWINGS + FBDS so...

We usually have an initial time and then find an equation for the variable final time. Can we derive a formula to calculate position with final time and variable initial time. ##v = v_i + a(t_f - t_i)## ##dx = v_idt + at_fdt - atdt## integrating ##x_f - x_i = v_i(t_f - t_i) + at_f(t_f - t) -...

I’m not sure of how to begin solving this problem. I attempted to draw a diagram and finding the components velocity of each initial velocity vector but this did not lead anywhere. Could so please have a hint?

Suppose two objects, A and B, with large lengths LA and LB, and masses MA and MB, collide at time t0. Both objects before collision are vertical and aligned concentrically, being object B positioned initially at a higher z coordinate than object A. The bottom end of object A is rigidly...

i want to build a forward kinematic model of a snake robot, to find its end-effector position am already worked on a few robotic arms like puma 560 using the DH table so i tried using the DH table on the snake robot, but it seemed wrong, so how do i do it ? the snake robot is similar to the...

Question: Galileo released a metal ball from rest so that it could roll down a smooth inclined plane. The time t taken to roll a distance s was measured. He repeated the experiment, each time recording the time taken to travel a different fraction of the distance s. Write an expression for the...

a) We use the definition of linear speed in terms of angular speed: v = r*omega omega_f = v/r = (1.25 m/s)/(0.025 m) = 50 rad/s omega_0 = v/r = (1.25 m/s)/(0.025 m) = 21.55 rad/s b) We use the definition of linear speed: v = d/t d = vt = (1.25m/s)(74 min)(60 s/1 min) = 5.55 km c) We use the...

I tried to write the data I understood from the image: y0=160m yf=0 x0=0 x1=192m I tried to express the total change in time using the position over time equation on the Y direction: y(t)=y0+v0y*(t2-t1)-0.5a(t2-t1)^2 but then I stuck with 2 variables and didn't know what to do any help?

The textbook (Nelson 11) at my school lists the "big 5" equations for uniform acceleration. In all but one, they use vectors. For vf^2=vi^2 + 2ad, the opt not to use vectors. Is there a deep reason why we would not want to use the vectors? I understand that when you square the velocity, the...

So what I have done is that on question 7 I know he is accelerating to constant my knowns are that it is from initial and acceleration is given so I have that for my first phase the second phase is that Your vfinal is your new initial for it and acceleration is the constant but you don't know...

this is my work but the answers say 11 m/s^2 so I made an error somewhere. Also if someone could help me with solving the direction for the acceleration, that would be greatly appreciated.

I calculated average velocity but obviously it helps nothing with this problem. I hope to get me going with these exercises once I break the ice. Thank you in advance!

If each ball rises two meters, then the time is in the air is equal to around 1.28 seconds. After this, what am I supposed to do? I feel really stuck. If all of the balls are released at different times, how am I supposed to find the answer?

The question I have is that if the aero plane is traveling in the same direction as the wind, would it not increase its velocity, as in with boats and streams? So, if by chance, ##w = v##, then the velocity of the aero plane would double. It feels weird as going by the same logic, if the speed...

Would we assume that the deceleration of both instance are the same?

We know that ##v = \omega r## where ##r = R_{\text{E}} + h##. To compensate for the motion, the plane must fly along the equator at the same speed as the Earth but in the opposite direction, i.e. from east to west, so $$\vec{v} = -\vec{ v}_{\text{E}}$$ $$v_{\text{E}} = \omega_{\text{E}}...

Hello, I understand that, for 1D kinematic problems where the acceleration function ##a_x## is initially given along with the initial conditions, we can use calculus (differentiation and integration) to get the position ##x(t)## and velocity ##v_x (t)## of the moving object. When the...

It's the body. So there's friction on that plane and there's tension also. $$L=\frac{1}{2}m_1\dot{x}^2+\frac{1}{2}m_2\dot{x}^2-m_2g(l-x)-m_1gx\sin\theta$$ $$f=\mu N=-\mu m_1 g\dot{x}\cos\theta$$ I had found the frictional force's equation from [the...

I hope the following questions relating to heading of this thread belongs to this forum.

This is jut an example to illustrate my doubt. I don't know how to obtain the tracjectory given only the acceleration in this format. I realized that if i can show that there is an constat vector 'a' that satisfy a•r=constant, than the motion would be on the surface of a cone. So i tried to make...

Show that a point with acceleration given by: a=c*((dr/dt)×r)/|r|3 where c is a constant, moves on the surface of a cone. This is jut an example to illustrate my doubt. I don't know how to obtain the tracjectory given only the acceleration in this format. I realized that if i can show that...

Im for some reason getting 1.58 s for time. I found 1.75 m as the head start distance and then I do d=d so: 2.45t^2 = 1.75t^2 +1.75 but the answer for "a" should be 6.45s...

I solved this and got 27.3 seconds so basically what I did was found the headtsart of the slower car (15.6 m/s times 6.65 seconds) but the answer given is 33.9 seconds and it uses the second (faster cars speed) to find the head start distance. Which answer is correct and why? Thanks so much

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i calculated the time difference between each marker, and using the first equation, i solved for V1. i then used this V1 as V2, time as the first marker (3.75) and used the second equation to solve for V1. is this method correct? can somebody please verify?

Hi! I can't solve this. Please someone give me a hint and help? I'm unsure what equation to use. Thank you!🙏🙏🙏 An artillery crew demonstrates its skill by firing a shell at an angle of 49 deg and then lowering the gun barrel and firing a second shell at a smaller angle of 20 deg in such a way...

1. $$x_{A}(t)=\begin{cases}\frac{1}{2}a_A t^2 & 0\leq t\leq 2.8\\ \frac{1}{2}a_A 2.8^2 +v_A t & t>2.8\end{cases}=\begin{cases}\frac{1}{2}a_A t^2 & 0\leq t\leq 2.8\\ \frac{1}{2}a_A 2.8^2 +a_A\cdot 2.8\cdot t & t>2.8\end{cases}$$ so ##x_A(5)=40## implies ##a_A=\frac{40}{17.92}m/s##. Similarly for...

Does the position of the origin for the body’s rotating coordinate frame 1) stay fixed to the moving body or 2) does it stay fixed to the inertial frame, yet still able to rotate as the body rotates with the only restriction that it cannot translate with the body i.e. only affixed at the...

0=6-4.9(t^2) 0=-27,7t+Xo From the first equation, T= 1.10s From the second equation, (Xo/27,7)=t 0=6-4.9((Xo/27,7)^2) We solve for Xo = 30,65 Now, we have X=-27,7t+30,65 If t=1,10 Then , -27,7(1,10)+30,65=0,18 which is not equal to 0. Which means the stone hits the ground first. Is my answer...

Hello! I have a somewhat complicated robot project that I've simplified here to hopefully get a quick answer. I want to build a robot with two omni-wheels that looks like the following (not drawn to scale), where the black is the omni wheels at 45 degree angles and the blue is the robot body...

I was taught that kinematics is the study of local motion without references to its causes (like forces, fields, etc.). That seems useful to say but perhaps it is not really that helpful. What are the kinds of kinematics? I can think of three kinds: classical kinematics (from mean speed to...

I had deduced that B,E,H are the places where acceleration will be zero, but when I read the solutions it showed that K also has a = 0. It said it had maximum slope and then said a = 0. But I couldn't understand why? Please help.

We have direct mass models of stellar motion inside of galaxies (basically, find a happy medium between a sphere and a disc). And of course dark matter corrections to explain the deviation between model and observation. Is there any pattern at all to the motion of extragalactic stars passing...

The way I tried to solve it is by using following reasoning. The inclined part of the string will each have a speed of U m/s. So the point P just above mass M where the inclined strings meet is being moved up by each inclined string at ##U \cos {\theta} ##. Therefore, the speed of the point P...

The point of confusion is deciding the direction each persons sets out in i.e. velocity direction of each person. Knowing this will probably help in getting the solution. At t=0, I can say that velocity of each person is as shown in diagram below.

By considering a vector triangle at any point on its circular path, at angle theta from the x -axis, We can obtain that: (rw)^2 + (kV)^2 - 2(rw)(kV)cos(90 + theta) = V^2 This can be rearranged to get: (r thetadot)^2 + (kV)^2 + 2 (r* thetadot)(kV)sin theta = V^2. I know that I must somehow...