Відео

I'm a physicist. For numerical results, I use an RPN calculator. I do have an HP-15C Collector's edition, but I prefer the clones from SwissMicros (they have a better keyboard, IMO), which is my standard (but it's expensive). There's also the HP-35S, which is a good one, but has some quirks (mostly the font they used, which makes it hard to read the comma and other things, plus some functions which do not work as expected in complex mode). If I need more, that is, graphing or CAS, I still have an HP50g (which is GREAT). Another one I can recommend is the HP Prime. It still has an RPN mode, but it doesn't quite work well. But the CAS and graphing part are spectacularly good. The software has some issues, which probably won't get fixed, since HP doesn't have a team anymore that can support and update it (such as the CAS using lower case x as default variable, the graph part using upper case X. So you cannot easily copy'n'paste a function from one to the other. This might be a requirement for schools to prevent cheating, though.) SwissMicros makes some clones of older HP RPN. The DM-42 is a clone of the HP-42 with updated software using 34 (!) (in words THIRTY-FOUR) digits. It's a beast! But they are expensive (the DM-15L, clones of the HP-15c, cost CHF 135 plus S&H).

Keep it up brooooo😊

On a Casio, press the [ENG] or [SHIFT] [ENG] key to display the result in scientific notation.

Motion of a ball y 2 dots = -g because my2dots + mg = 0

Hamiltonian means Kinetic energy + potential energy right....why are you use lagrangian in Hamiltonian

In high jump you have to move your centre of mass over the bar (as well as the rest of your body), so from that point of view the idea she jumped 3.5 metres high is ridiculous. The women's world record in high jump is 2.10 m and the record holder's height is 1.80 m. Assuming her centre of mass is at 0.9 m, she would have jumped 1.2 m. So the 2.6 m at 1.4 m (0.7 m CoM height making it a 1.9 m jump) is impressive but without a doubt supported by the floor.

As a mechanical engineer, I was puzzling over how Ms. Biles could leap so high so thank you for quantifying this, Rhett. (You are a youtube treasure, in my opinion.) As my family and I watched the gymnastics competitions and the 12' numbers were being shown, I was wondering if the gymnasts somehow benefit from the springiness of the floor. Then again, as the other respondent thus far has noted, high jumpers slightly exceed the vertical leap of the gymnasts without any possible floor springiness. Any thoughts?

great as usual , can you plz make a playlist of your old python videos than have some advanced topics like quantum mechanics and numerical methods of solving in physics

Integrating data collected from a phones accelerometer over more than 2 seconds is naive ... You would never get anywhere closer to correct estimates ... Thats why there is GPS, Barometer which can rectify the calculation errors occuring over larger measurements.

Have you ever had a signal made out of hydrogen

How are L4 and L5 created?

Hello. This video is very insightful, is there any maths to calculate the deflection of the asteroid after being hit with a rocket

Nice

Does the centrifugal force acting outwards on the vehicle, due to angular velocity/acceleration, act parallelly along the inclined plane (parallelly opposing the frictional force) or does it act just parallel to the x-axis ? If it is the former, wouldn't that force need to be resolved as well ?

I thought that when an object is in free fall it is following a geodesic which by definition means the object is not accelerating? And that when it is resting on the ground it is accelerating upward?

Thoroughly enjoyed your lecture. I have initial position, linear and angular velocity vectors(also spin rate). Finding difficult to get a trajectory. Using right handed coordinate system where gravity acts -Z direction. I would be glad if you can share a video on 3 d projectile motion with air drag and magnus effect. Thankyou 🙏

Good that you made mistakes and went through and fixed them. It shows the true process of these sorts of methods

Super analysis!

Yeah, these are always tricky to use, so this was a good intro. 👍

Good lecture. I like it.

great video and sound quality was good thanks i was in a trouble for L3

So I know the basic force formula, but how would you figure out the force of an object moving at a constant speed hitting another object that isn't moving? Say a car traveling at 60mph hitting a wall? Would you have to use the deceleration as "a" in the formula? Or is there a way to calculate it with just speed?

Since you're good at physics, can you see my beach ball video for a geometrical view?

Take zero dimensions and define it as a point. Take one dimension and call it a joint between two points. Two versions of a second dimension: the first is joints between a third point and the second is the direction between two points. Begins to explode into silliness when you then try to define a third dimension including direction and even direction's inverse.

f1 cars are rwd so your conclusion seems correct

Thank you for the code! Here is a modified version so that it plots displacement-time, velocity-time and acceleration-time graphs for any scenario that may occur for a damped oscillator (undamped, underdamped, critically damped or overdamped. Hope this helps: GlowScript 3.1 VPython # Create graphs for displacement, velocity, and acceleration graph_width = 600 graph_height = 400 disp_graph = graph(xtitle="Time [s]", ytitle="Displacement [m]", width=graph_width, height=graph_height) vel_graph = graph(xtitle="Time [s]", ytitle="Velocity [m/s]", width=graph_width, height=graph_height) accel_graph = graph(xtitle="Time [s]", ytitle="Acceleration [m/s^2]", width=graph_width, height=graph_height) disp_curve = gcurve(color=color.magenta, label="Displacement", graph=disp_graph) vel_curve = gcurve(color=color.orange, label="Velocity", graph=vel_graph) accel_curve = gcurve(color=color.cyan, label="Acceleration", graph=accel_graph) # Initial setup L0 = 0.2 anchor = sphere(pos=vector(-L0/2, 0, 0), radius=0.01, color=color.yellow) mass = sphere(pos=vector((L0/2+0.02), 0, 0), radius=0.02, color=color.red) mass.m = 0.02 k = 2 mass.p = mass.m * vector(0, 0, 0) spring = helix(pos=anchor.pos, axis=mass.pos-anchor.pos, radius=0.01, thickness=0.005) # Time setup t = 0 dt = 0.001 # Select damping type damping_type = "critically_damped" # Choose from "undamped", "underdamped", "critically_damped", "overdamped" # Set damping coefficient based on damping type if damping_type == "undamped": c = 0 elif damping_type == "underdamped": c = 0.025 # Adjust to be less than critical damping elif damping_type == "critically_damped": c = 0.4 elif damping_type == "overdamped": c = 5 # Adjust to be greater than critical damping # Initialize previous values for calculating derivatives previous_displacement = mag(mass.pos - anchor.pos) - L0 previous_velocity = 0 # Initialize buffers for central difference method displacement_buffer = [previous_displacement, previous_displacement, previous_displacement] velocity_buffer = [previous_velocity, previous_velocity, previous_velocity] # Simulation loop while t < 10: rate(1000) # Calculate forces L = mass.pos - anchor.pos Fs = -k * (mag(L) - L0) * norm(L) Fv = -c * mass.p / mass.m Fnet = Fs + Fv # Update momentum and position mass.p = mass.p + Fnet * dt mass.pos = mass.pos + mass.p * dt / mass.m # Update time t = t + dt # Update spring properties spring.axis = mass.pos - anchor.pos # Calculate current displacement current_displacement = mag(L) - L0 # Update displacement buffer displacement_buffer[0] = displacement_buffer[1] displacement_buffer[1] = displacement_buffer[2] displacement_buffer[2] = current_displacement # Calculate velocity as the central difference of displacement velocity = (displacement_buffer[2] - displacement_buffer[0]) / (2 * dt) # Update velocity buffer velocity_buffer[0] = velocity_buffer[1] velocity_buffer[1] = velocity_buffer[2] velocity_buffer[2] = velocity # Calculate acceleration as the central difference of velocity acceleration = (velocity_buffer[2] - velocity_buffer[0]) / (2 * dt) # Plot displacement, velocity, and acceleration disp_curve.plot(t, current_displacement) vel_curve.plot(t, velocity) accel_curve.plot(t, acceleration) # Update previous values for the next iteration previous_displacement = current_displacement previous_velocity = velocity

Thanks so much , I wasn't sure as to whether the direction of the change in velocity was towards the centre of the circle or not and thanks for clarifying it.

Thanks this is very helpful :)

Try putting trinket in your shirt pocket...

Clear button??? "CLX"...

I started off with an expensive programmable TI calculator then soon switched over to an HP-15C an never looked back. PRN is the way to go hands down...

So much easier with an HP-15C calculator...much fewer keystrokes...

Hi sir, I like your videos they are really quite helpful and easy to understand. I think it would be really helpful if you could arrange the playlist in a much ordely manner or attach links to similar videos you've made 🙏. And thanks a lot for you help, God bless you.

I'm working on a picture of two guys playing catch with a beach ball. If I post a picture on my channel, will you check it out and share your geometrical/physics-based perspective? Of the ball's direction and the angle of the two throwers?

aha at 10:38 it's y''=-g not y''=g, since we defined the ground to be 0 and the sky to be positive.

Hello. Do you have takeoff.xls available? Thank you very much

@17:10 It didn't travel the same distance as it did when you shot it straight out. It is 7.85e6 straight out versus about 7.28e6 at the 45 degree angle..

Moment of rigid bidy about a fixed axis

how do u install on pycharm

Explained capitalism perfectly

LOVED the spring compression!

Keep moving forward!

Difficult but easy!

I can't give this video a thumb up. For years I've been telling my students to always write down the units as well as the numerical values. s != sqrt(0.06), but s = sqrt(0.06) m. One of the reasons I gave was that s is a length so it has units of lengths but the the right side of the "equation" there is just a number. And that can't be equal. A quantity with dimension of length, for instance, is never equal to (=) a number. Second, and more import reason, if you've made any mistakes you can check your equation using the units. Whatever is on the right must be equal to what's on the left. So write down your units and than make sure that the dimension on both sides is the same. Problems like 7:20 can easily be avoided. which is particularly important in an exam. So, videos like this destroy in 30 minutes what I try to fix for years.

thanks really needed to know how to use polar co-ordinates in questions

I believe keeping the mistake is beneficial. First, evaluate your answer at the end by asking, 'Does this make sense or fall within an acceptable range?' If not, calmly review your units and check your calculator. Once you realize the mistake was due to a calculator error, it's easy to correct it. This approach isn't just for physics; learning how to THINK and ANALYZE is more important than merely solving a problem. This process mirrors the scientific method: asking a question, conducting an experiment, and evaluating the results. I didn't fully understand this until about two years after my first physics class because I was focused solely on finding a solution. BTW that Vpython program is really sick! My Physics 1 and 2 course used Vpython as well! I could not have programed that as fast as you like wow that was impressive!

Many thanks! There is an obvious mistake at 10:25 . You've lost te sign. There y double dots should be equal to minus g

I can do it, I’ll send my webpython code.

Predator/Prey problem, and really interesting 🐺 🐇

Let d = initial distance between them, W = speed of Wolf, H = speed of Hare. The time it takes the wolf to capture the hare is given by average of i) time when they move towards the other [d/(W+H)], and ii) time when they move away from the other [d/(W-H)]. For d= 15m, W= 4.5 m/s, H=3m/s, we get t = 0.5(15/7.5 + 15/1.5) = 0.5(12), so t = 6 seconds. Note: equation for time of capture is only valid if the initial velocities are perpendicular.