Average Definition and 1000 Threads

I have 10 sets of data which I have to analyze. The data represents a change in voltage over time and I want to come up with an "average" curve to represent the 10 sets of data. The problem is that the time index for each data is different so I can't simply average the voltage. Is there any...

Homework Statement Starting from rest, a subway train first accelerates to 25m/s and then begins to brake. Forty-eight seconds after starting, it is moving at 17 m/s. What is its average acceleration in this 48-s interval? Homework Equations 1. v=v0+at 2. x=x0+(1/2)(v0+v)t 3...

Hey all, Directed towards those of you that have tried, finished or are trying to get into a (US) graduate program (physics, but not necessarily); how long before the test did you start studying. I know in the case of physics the test is mostly lower division knowledge, but I'm just curious...

Homework Statement Question 26 of the physics GRE from the practice test available here: https://www.ets.org/gre/subject/about/content/physics/ The normalized ground state wave function of hydrogen is \psi_{100}=\frac{2}{(4\pi)^{1/2}a_0^{3/2}}e^{-r/a_0}, where a_0 is the Bohr radius. What is...

"Average Randomness" Thought experiment Please bear with my explanation, I am, by no means a Physicist. During a recent theoretical thought experiment, I thought of a strange factor that I feel I should let out before it becomes forgotten by the constant wave of thought experiments that flow...

I just want to make sure I'm understanding negative work correctly. An example problem where there is a bullet with an initial velocity of x m/s and a final velocity of 0 m/s. It is stopped by a wood block and the question asks to determine the amount of work done on the bullet by the block. If...

I'm trying to find the average velocity of a spinning propeller. v(r) = RPM C(r) / t ; C(r) = 2πr; t=(1 min) v(r) = RPM 2πr / (1 min) I'm not quite sure what to do next. I need the answer in units of velocity, but if I integrate that last equation, I won't get units of velocity. My rough...

Homework Statement An object traveling at a constant velocity v0 experiences a constant acceleration in the same direction for a period of time t. Then, an acceleration of equal magnitude is experienced in the opposite direction of v0 for the same period of time t. What is the object's final...

Homework Statement The thermal conductivity of Cu at room temperature is 400 W/(mK). Use this value to determine the average time between collisions, \tau. Compare this value with the electrical conductivity.Homework Equations Not sure. I take T=300K for room temperature. From a book and with...

Homework Statement A solenoid of length 20.0 cm is made of 5000 circular coils. It carries a steady current of 10.0 A. Near its center is places a very flat and small coil with a resistance of 2.50 Ω made of 100 circular loops, each with a radius of 3.00 mm. This small coil is oriented so that...

Homework Statement A Bus drives 1km up a hill in 5.0 minutes. It then drives down the hill in 4.0 minutes. For the bus, find a) the average speed up the hill b) the average speed down the hill c)the average speed for the whole trip d)why is the answer for c) not equal to (speed up the hill +...

I really like Mathematics and wondering for the salary for a new assistant professor in the subject.

Homework Statement In each batch of manufactured articles, the proportion of defective articles is p. From each batch, a random sample of nine is taken and each of the nine articles is examined. If one article is found to be defective, the batch is rejected; otherwise, it is accepted. If...

Consider a set of n numbers, and let their arithmetic mean be X. Suppose a new number Y, is added to the set. Prove that the mean of the new set, with (n+1) members, is between X and Y. I've been trying to prove this the past few minutes, but I think I'm at a dead end. It's a problem that...

A 52.0-g Super Ball traveling at 28.0 m/s bounces off a brick wall and rebounds at 16.5 m/s. A high-speed camera records this event. If the ball is in contact with the wall for 3.60 ms, what is the magnitude of the average acceleration of the ball during this time interval? Im not really sure...

Homework Statement Unlike the older vinal records which rotated at a constant ω of 33.3 rotations per minute (rpm), compact disks vary their rotation speed during the playing period. A certain CD has a diameter of 12cm and a playing time of 79 minutes. When the music starts, the CD is rotating...

Let's I have three values, 3.30±0.1, 3.32±0.1, and 3.31±0.1. How would I find the uncertainty of the average of these values?

e.g. pushing a door with x-lbs of resistance, assuming a person is exerting force perpendicular to the door, 36" from hinge. What is that x-lbs (max) an average adult could pushing with ease? Thanks

My friend and I were discussing particle accelerators (betatrons to be exact) and we began to argue about the size of the core magnets and vacuum chamber. He said that an average torodial vacuum chamber is 0.5m. I have seen old photos of them and said that's more likely to be the diameter. I...

Homework Statement NASA operates a 2.2 second drop tower at the Glenn Research Center in Ohio, where experimental packages are dropped from the top of the tower. a) What is the drop distance of a 2.2 s tower? b) How fast are the experiments traveling when they hit the airbags at the bottom...

A race car driver must average 200.0 km/h over the course of a time trial lasting ten laps. If the first nine laps were done at 198.0 km/h , what average speed must be maintained for the last lap? Avg Speed=Distance traveled/Time 218 km/h, I averaged the first 9 laps at 198 and plugged the...

I have the function: f(x,y)= x*(y^2)*e^-((x^2+y^2)/4), with x and y from -3 to 3 I took the integral of this function and got 0 as my answer. I need to find the average value, which is 1/area multiplied by the double integral. Since the double integral is 0, would the average value also be...

Homework Statement I can't answer to that question, and I don't know how to. I have to calculate the average separation between H2O molecules in pure water. Homework Equations The diameter of the molecule is 0.29 nm I think we can use the bohr equation to resolve it? r = (ε0*h2)...

During 12 s an engine increases the speed of a 1.5×103-kg vehicle from 13 m/s to 27 m/s. Assuming no losses, what average power is the engine producing? P = W/t W=FΔx W=ΔKE ΔKE=mvf2-mfi2 I tried finding the change in kinetic energy to solve the problem, but it didn't work. I got 3.4E3...

I put this under statistics because of your knowledge of the Gaussian. I have run into an elementary problem. I was considering what the average value, <x>, is for a Gaussian with an x offset, and got results which don't make sense to me. First, it is obvious that for P1(x)=e^(-(x^2)) the...

The velocity of a river varies parabolicly with V adjacent to the banks and max velocity d halfway betwee the banks. The flow of river is parallel to the bank. The width of the river is x. How do you calculate the average velocity?

I have some question about Ensemble Average. The macroscopic variable of fluid is average of microscopic variable of gas molecule. And if time average is same with spatial average I know as it called edgodic. My question is that if two different microscopic variables which have same...

Hi everyone, What is the difference between an expectation value and an average. I may have this wrong, but is it something along these lines: You perform a series of measurements on a given observable, such as momentum, and the average value of all these measurements is your expectation...

Homework Statement The gases in this room include oxygen (molar mass 32 g), nitrogen (28 g), water (18 g), and carbon dioxide (44 g). Which type of molecule has the highest average speed? A) O2 B) N2 C) H2O D) CO2 E) They have the same average speed. Homework Equations...

Homework Statement A particle of mass m moves in the potential energy V(x)= \frac{1}{2} mω2x2 . The ground-state wave function is \psi0(x)=(\frac{a}{π})1/4e-ax2/2 and the first excited-state wave function is \psi1(x)=(\frac{4a^3}{π})1/4e-ax2/2 where a = mω/\hbar What is the average value of...

Hello, The entropy of the Grand Canonical Ensemble (GCE) is: S = KB ln ZG + (\bar{E}/T) - μo\bar{N}/T Helmholtz function is: F = \bar{E} - TS = \bar{E} - TKB ln ZG - \bar{E} + μo\bar{N} = -TKB ln ZG + μo\bar{N} But \partialF/\partialT = -S (From thermodynamics). Then...

Hey, I attend Georgia Tech and I am completing my freshman year here. I am probably going to end up with a 3.1 - 3.3 GPA this year. I was wondering whether this is poor, average, or good. Keep in mind that my major is Electrical Engineering which is considered to be one of the hardest majors at...

A body covers half its journey with a speed of a m/s and the other half with a speed of b m/s Calculate the average speed of the body during the whole journey

Natural selection: What do they mean by "average" individual? You know how they say stabilizing selection favors the "average" individual - i.e, it is centered around the mean? I have a question. How do they calculate this "mean"? I'm confused. All I know is that if pure-white rats mate...

Hi, I would appreciate any help with the following: The coil in a loudspeaker has an inductance of L = 112 microH. To produce a sound of frequency 40kHz, the current must oscillate between peak values of + and - 4.4 A in half a period. What average back emf is induced in the coil during this...

Homework Statement find the average value of (1+4z)**3 on the surface ... Homework Equations The Attempt at a Solution All I really want to know is how to go about this? Is the average value on the surface just the surface integral over the area of (1+4z)**3?

I was given this question in a practice assignment; A 31.0 kg child on a swing reaches a maximum height of 1.92 m above her rest position. Assuming no loss of energy: 1.At what point during the swing will she attain her maximum speed? 2.What will be her maximum speed through the...

As we know , the average value of a function over is : i wanted to calculate the average value of a function over its entire domain ( e.g ) firstly, i divided the interval into 2 intervals & and calculated the F_avg for each ,,, is my way correct ? thanks !

Homework Statement A typical flying insect applies an average force equal to twice its weight during each downward stroke while hovering. Take the mass of the insect to be 10 g, and assume the wings move an average downward distance of 1.0 cm during each stroke Assuming 100 downward strokes...

I've a set of tests, and for each test, they have different size. I'll show an example. Test1 size - Time(seconds) 100 - 10 100 - 23 100 - 17 200 - 37 200 - 42 200 - 47 300 - 53 300 - 53 300 - 53 For each test, I took the average. Average1 size - average 100 - 16...

Homework Statement A car traveling at 85km/h strikes a tree. the front end of the car comoresses and the driver comes to rest after traveling 0.8m. Homework Equations a) What was the average acceleration of the driver during the collision? b) Express the answer in terms of g's ; where...

Homework Statement A parable is f(x) = 0,01x2-2x+100 it beginswith the cut with the y-axis and ends when it cuts the x-axis. Questions : a) find the average slope of the parable. b) Find the place on the parable where the average slope is present. Homework Equations here i...

I have been solving these sort of problems, and they follow this basic paradigm: first, they will tell me I traveled a distance D at a velocity of A, then they traveled the same distance D at a velocity of B. Why can't I simply just simply perform the following computation: (A+B)/2. I have been...

Homework Statement A 89.6 kg man steps off a platform 4.52 m above the ground. He keeps his legs straight as he falls, but at the moment his feet touch the ground his knees begin to bend, and, treated as a particle, he moves an additional 0.88 m before coming to rest. Treating our rigid...

There are n people with masses mn . Each run up a given slope of height h in times tn. Gravitational accelartion, g, is constant. Now there are 2 ways to calculate the average power of this group of people with 2 different results. The question is which way of calculating the average power...

Homework Statement I believe I understand the problem except I cannot get the time average of [sin(wt-d)]^2 = ½ I can do the rest once this is established. Homework Equations Average of a function= <function>= 1/(period)* integral(f*dt) from 0 to the period Function to be...

Homework Statement Find average value of Normal Acceleration from the information given. (See the picture) Homework Equations a^{→}_{ave}= Δv^{→}/Δt a_{t}=Δv/Δt The Attempt at a Solution I took the difference of the given angles in radians and divided it twice by Δt and get...

Hello! In order to calculate wave run-up for a reservoir, I need to determine the average reservoir depth along fetch line (D).... Does anyone know how can I calculate this depth? In some book I have read that D is the average reservoir level along the direction of wind blow, and it is...

Homework Statement A closely wound rectangular coil of 95.0 turns has dimensions of 29.0 cm by 40.0 cm. The plane of the coil is rotated from a position where it makes an angle of 39.0 degrees with a magnetic field of 1.60 T to a position perpendicular to the field. The rotation takes 0.120 s...

I just need some clarification. In a lab that i did, a metal ball goes down a slanted ramp, onto a horizontal ramp of d distance, and then goes airborne (off the table). The instant the ball enters the horizontal ramp a timer is started, and - when it goes airborne - the timer is stopped. Thus...