Dissipation Definition and 184 Threads

QUESTION: R1 = 2 ohm R2 = 5 ohm What value of R3 maximizes the dissipation rate in resistance 3? (battery is ideal -> no internal resistance) DIAGRAM: _______________ |...|...| R1...R2...R3 |...|...| _ +...|...| - -...|...| |...|...| _______________ Someone posed this question...

Homework Statement A hockey puck B rests on a smooth surface of ice and is struck by a second puck A , which was originally traveling at 40.0 m/s and which is deflected 30.0 degrees from its original direction. Puck B acquires a velocity at a 45.0 degree angle to the original direction of...

Homework Statement Homework Equations P=F*V The Attempt at a Solution why isn't it P = Cd(A^2)(v^2) * (v) i don't see what i could do

Hi there Can anyone provide me with an explanation of what a wavenumber is, and how it can be used in determining the extent to which energy is dissipated during turbulence (ideally in the context of the ocean)? I am aware of the basic definition of a wavenumber (i.e. the reciprocal of wave...

Homework Statement a wire of resistance r is drawn to double its length. assume a constant voltage and a fixed volume, by how much does the power dissipation change? Homework Equations P=LEI E=V/L I=V/R The Attempt at a Solution so when i plug in 2L for L, it just ends up...

On a greasy, essentially frictionless lunch counter, a submarine sandwich of mass 0.500 kg, moving with speed 3.50 m/s to the left, collides with a grilled cheese sandwich of mass 0.200 kg moving with speed 2.00 m/s to the right. How much mechanical energy dissipates in the collision? I...

Homework Statement An outfielder throws a baseball with an initial speed of 71.0 mi/h. Just before an infielder catches the ball at the same level, its speed is 85 ft/s. How much of the ball's mechanical energy is dissipated by air drag? (The weight of a baseball is 9 oz.) Answer is asked for...

Homework Statement The corroded contacts in a lightbulb socket have 5.0 Ohms of resistance. How much actual power is dissipated by a 100 W (120 V) lightbulb screwed into this socket? Homework Equations P = V^2/R V = IR P = RI^2 The Attempt at a Solution I found the resistance of the lightbulb...

My colleague and I are having a debate and would appreciate your opinion. The question is: How much of the power consumed by a disk drive is thermally dissipated to the surroundings? My answer is very nearly 100%. The only energy that isn't thermally dissipated is a small amount of...

Homework Statement Block A of mass, mA = 2.0 kg, is moving on a frictionless surface with a velocity of 5.0 m/s to the right and another block B of mass, mB = 8.0 kg, is moving with a velocity of 3.0 m/s to the left, as shown in the diagram below. The two block eventually collide. d. If...

Homework Statement An open top railroad car (initially empty and of mass M.) rolls with negigible friction along a straight horizontal track and passes under the sprout of a sand conveyor. When the car is under the conveyor, sand is dispensed from the conveyer in a narrow stream at a steady...

Hi, I'm trying to evaluation the voltage of an RC circuit as it is dissipating a stored charge. Actually trying to do this under two different situations. The first is let's say the circuit has reached steady state for a given input voltage, Vo. Now I reduce the voltage instantly to some...

Homework Statement 1.) A 70kg boy runs as fast as he can up a flight of stairs which has vertical height of 10metres. He achieves this in 8 seconds. Calculate the average rate of energy transfer into gravitational potential energy that must have occured. 2.) A700kg car traveling at 20ms-1...

[SOLVED] Power plant Hi! Here i have a problem : A power plant generates 400 MW of electric power.It has an effieciency of 40%. a) At what rate does it dissipate heat? b)If the waste heat is carried away by a river, and the temperature rise of the river must not exceed 3°C, what flow rate is...

I need to design a circuit to charge a capacitor with minima loss of dissipation through resistance. Any idea?

Homework Statement Imagine a right angled triangle ABC. AC is the hypotenuse. The actual problem is: An inlined plane is kept along AC (5m metre long). An object A is kept at the base of it. A force is applied on it parallel to AC. AB is 3m long. Account for the difference between the...

This isn't really a "homework" question, this is just a question that a friend and I came up with a few months ago. I'm currently in grade 11 taking physics 11 honours, and far above the rest of my class :smile: :smile: :smile: Let's just say, IF the sun teleported instantaneously to a far...

Homework Statement Need to energy dissipation by the drap force on a ball in free fall from height h and when it has reached terminal speed, assuming it happens before it hits thr ground. Drag force has magnitude bv^2, where b is drag coefficient and v is instantaneous speed of the ball...

I have begun modelling a basic braking system in Simulink/Matlab for my final year project. The model is designed from the time force is exerted to the pedal at a particular velocity, to when heat is produced from the frictional force between the brake pad and disc. I have the modelling...

Homework Statement See Attachment. Find the total Current in the following circuit by phasor diagram techniques only. What is the total power dissipated?Do not use complex #'s. Homework Equations The Attempt at a Solution Im not really sure how to start and the notes for...

Homework Statement Three series elements have a.c. voltages across them of 25cos(2 \pi 60t + 30') , 15cos(2 \pi 60t + 60') , 30cos(2 \pi 60t -45') Volts respectively. The current flowing is 5.2cos(2 \pi 60t + 25')A Using phasor diagram find a)total voltage b)phase angle between...

I was asked to first find a few things using supersposition (A few voltages). Now it says to find the TOTAL power dissipated and there are two answers. Do I just find out all the currents(to find out all the voltages across each resitor)etc...and then sum up all the \frac{v^2}{R}'s for both of...

Homework Statement A LR circuit has a 10V battery, 5.50H inductor, and a 6.7 Ohm resistor. The battery is closed at t=0. (a) What is the time constant of the circuit? (b) How much energy is delivered by the battery during the first 2 seconds? (c) How much of this energy is stored in the...

QUESTION: R1 = 2 ohm R2 = 5 ohm What value of R3 maximizes the dissipation rate in resistance 3? (battery is ideal -> no internal resistance) DIAGRAM: _______________ |...|...| R1...R2...R3 |...|...| _ +...|...| - -...|...| |...|...| _______________ (I hope the diagram is...

Greetings all... When I pull a fairly good size/quality rubber band and then quickly hold it against my lips, I feel it to be quite hot. I assume that some of the energy used in stretching the rubber band is converted into heat by virtue of the properties of a "rubber band" My question is...

Hi all, I am trying to design a low power dissipation driver circuit. Basically the circuit gets a 1v digital signal which tells it whether to apply a separate DC power source of 100v across a 1nF capacitor. This digital signal is modulated at about 100kHz and will change at about 50kHz...

I have a question: 2 glass containers have the same amount of a particular acid. In one container, drop a fully compressed spring retained in the compressed state by some means. In another container, drop a similar spring, in its free form. The acid in the containers start to dissolve the...

If you have a globe marked 70W and 240V and you connect it to one end of cord( which has two wires, each of 0.6 ohms), and the other end of the cord is connected to a 240V outlet, what is actual power dissipated by the globe?

Hi all, (this has originally been in the Materials and Chemical Section. I think it does not belong there). I'd like to add a question heat dissipation from a brake bad. Basically, let's assume a brake pad is pressed against a surface that quickly moves along (can be the bicycle brake pad...

I have this flow field in cylindrical coordinates of which I would like to calculate the dissipation as a function of these coordinates. Now in my fluid dynamics notes I found the following expression(s) for the dissipation: 2 \mu (e_{ij} -\frac{1}{3} \Delta \delta _{ij} )^2 = 2 \mu (...

OK someoone on a different forum said his refrigerator is an 80 watt refrigerator (small lil college fridge). As in it takes 80 watts from the wall. Isnt it true that this isn't the same amount of heat that can be taken out of the contents inside? I remember someone talking about an...

An L-R-C series circuit with an inductance of 0.116 , a resistance of 235 , and a capacitance of 7.25 carries an rms current of 0.453 with a frequency of 393 . The phase angle is .776radians. The power factor is .714 The impedance is 329ohms The rms voltage is 149V The average power is...

Can anyone help me get started with this problem: A 50kg man at a water park shows off by going down a long, winding waterslide of varying slope. THe slide is a total of 25m tall from start to finish, and the man starts from rest. DEspite all the attempts to minimize friction with rushing...

Anyone have a link or direct info regarding the rate at which the Earth's atmosphere dissipates into space? I'm looking for both an estimate of the current rate as well as a model (time and mass dependencies). Thanks.