In physics, work is the energy transferred to or from an object via the application of force along a displacement. In its simplest form, it is often represented as the product of force and displacement. A force is said to do positive work if (when applied) it has a component in the direction of the displacement of the point of application. A force does negative work if it has a component opposite to the direction of the displacement at the point of application of the force.
For example, when a ball is held above the ground and then dropped, the work done by the gravitational force on the ball as it falls is equal to the weight of the ball (a force) multiplied by the distance to the ground (a displacement). When the force F is constant and the angle between the force and the displacement s is θ, then the work done is given by:
W
=
F
s
cos
θ
{\displaystyle W=Fs\cos {\theta }}
Work is a scalar quantity, so it has only magnitude and no direction. Work transfers energy from one place to another, or one form to another. The SI unit of work is the joule (J), the same unit as for energy.
let ##f : R^3 → R## the function ##f(x,y,z)=(\frac {x^3} {3} +y^2 z)##
let ##\gamma## :[0,## \pi ##] ##\rightarrow## ##R^3## the curve ##\gamma (t)##(cos t, t cos t, t + sin t) oriented in the direction of increasing t.
The work along ##\gamma## of the vector field F=##\nabla f## is:
what i...
Why work done is area enclosed by graph of F v/s x on x Axis but not y axis.
Suppose we apply a force on object which is proportional to displacement as ##\vec f##=## \vec x##²then area enclosed by Force and displacement on x Axis is integral of ##\vec x##²but on y-axis it should be integral of...
Just curious if anyone out there is using the old low pressure sodium vapor lamps for spectral calibration and diffraction work. I was surprised that I do not see any bench ready laboratory lamps from the usual vendors. I understand that the last manufacturer of the low pressure bulbs, Philips...
Here is the question:
I have correctly calculated the power produced by the thrust force (P = Force x Velocity = 9.0 × 104W) , the work done by the thrust force over 3 minutes (W = Power x Time = 9.0 × 104 × 3.0 × 60 = 1.6 × 107 J) , and the gain in potential energy over this period (mgh =...
All I know is that when you press the button, the LCD icon displays an alarm icon which indicates the alarm has been programmed to sound at the exact time every 24 hours.
What do I see in my solution is :
ΔW + ΔQ = W_pv + W' + ΔQ (A little difficult to perceive the useful work )
Work on the environment : -p0*(-ΔV) (WHY negative sign?, Is this the work ON the gas?)
ΔV=nR (T0/p0 -T/p)
By TdS = dQ
ΔS + ΔS0 =0
Reversible case:
ΔU= -T0ΔS - (-p0(-ΔV)) + W' (WHY...
Pardon if this is easy to find but I tried google with little success,
so how can a fast reactor work without a moderator? Now I understand that a moderator is commonly used within thermal reactor which is why they are thermal in the first place as the neutrons get slowed down and their energy...
When we say that we apply force to a wall then we didn't transferred energy because of no displacement, but I think we somehow increase many types of energy of the wall. For e.g:- potential energy of particles in wall e.t.c.
So according to me it means that we defined work only for mechanical...
Hi All,
I am working on an engineering problem, where i have to calculate the total work needed to compress a volume of air (Locked in a cylindrical chamber similar to an IC chamber where the piston moves to compress the air mixture)
I am defining the process with the below initial...
A year ago, we switched to Consumer Cellular. Since then, my wife and I have been getting Amber Alerts for the state of Colorado. We live in Florida, and Vermont. Our area codes are 518. We have no connection to Colorado.
I just talked with Consumer Cellular customer service. They say...
A recent thread posed the question whether work is done by static friction in the case of an accelerating car. Before I had a chance to reply, the thread was closed on the grounds that the subject was "beaten to death". Undaunted, I am determined to deliver the coup de grâce here with a simple...
Hi there
I have been attempting the parts to this question and I'm finding some trouble on how to answer the last part which is d)iii
Here is what I have done for the rest of the parts and what I think I should start off with in part d)iii
Thanks!
In textbooks or in lectures it is said that : Work can be either positive or negative: if the force has a component in the same direction as the displacement of the object, the force is doing positive work. If the force has a component in the direction opposite to the displacement, the force...
I was reading the chapter kinetic energy and work where I saw a derivation in which it was proved that work done=change in kinetic energy, so i understood from this derivation that work done is energy transfer by means of force but in this book kinetic energy is introduced earlier so as to find...
I'm asking for clarification, but it's my understanding, that of the thread below, and my college physics book Paul A tipler, that when walking or driving a car, the force of friction from the ground does no work. This makes sense in a car becuase the engine/fuel makes the power, driving the...
I found two formulas to calculate the work done. One is with this path integral:
## W_{AB}## = W(## r_A,r_B ##)=q* ## \int_{r_A}^{r_B} E*dr ##
but here is the one I tried to use:
## W_{AB}## = q*Δ U = q*(## \frac {kQ} {r_A} ## - ## \frac {kQ} {r_B} ## )
Now here's my problem, what are...
I have a problem which consist in 1 bit RAM made of 3 MOSFETs. One of the questions is to calculate the maximum voltage that the memory element can receive. I have obtained the result by inspection (it is 4 Volts) but I'm unable to reach the same by applying the Thevenin Theorem.
My...
From what I understand, constraint forces do no work because they are perpendicular to the allowed virtual displacements of the system. However, if you consider an unbalanced Atwood machine, in which both masses are accelerating in opposite directions, you'll find that the tension force of the...
When calculating power, which is Work/time, do we consider NET work (work calculated based on net force) or just work done by the individual force that goes in the same direction as the displacement?
If it's the first, then power is 3W.
If it's the second, then power is 5W.
Which one is correct?
Apologies for my fairly undescriptive title, I'm having trouble coming up with a better one.
I'm simply trying to verify whether my understanding of this problem is correct.
1. Pushing the oven up a ramp 4m long would require more force (my reasoning here is based on the results of a lab which...
I'm having a little trouble with part a) of this question:
Since it is stated that the heating is slow, I thought it was reasonable to assume the process is reversible which means that the pressure in both sides should be equal. Consequently, $$W = - \int_{V_{0}}^{V_{1}} P dV = -...
According to the first principle of thermodynamics: ΔU = W + Q
Also noting that: W = -P⋅ΔV (Question: This P is the initial pressure or the final?)
To find V2:
(P1⋅V1) / T1 = (P2⋅V2) / T2 → Therefore, (P⋅V1) / T1 = [(P/5)⋅V2] / T2 → (P⋅V1) / T1 = (P⋅V2) / (5⋅T2) → V2 = (5⋅T2⋅V1) / T1...
Have had a try at answering this question, and want to particularly know if I had done part e) correctly
Here is my workings from the previous parts as I need to use some prior values that I have obtained before to do part e)
For the last part, there were 2 ways that I went about it...
The proof of magnetic forces do no work is given in Introduction to Electrodynamics by David J. Griffiths like this
My problem is why he has replaced d\mathbf{l} with \mathbf{v}dt? This substitution implies that the charged particle was moving with \mathbf{v} only and no force acted on it...
Here's my attempt for the first part:
For the first body, the work obtained is
##W_1 = C_P (T_1 - T_f)##
while for the second body, it is
##W_2 = C_P(T_2 - T_f).##
So the net work obtained is the sum of these two:
##W = W_1 + W_2 = C_P (T_1 + T_2 - 2 T_f)##
and that proves the first part...
What is the principle of operation of a quantum computer on a silicon chip? What are a qubits and how they connected and interacted between themselves? How does CMOS technology work in a quantum computer?
Since the assignment asks the work done by the gas, that should be equal to P1*(V2-V1) aka the area under the P1 line. Do I have to subtract the work done to the system or is this the solution already? If so, why do I need P2?
I know that you can get the answer through using Fs as 18 and solving for K, then subbing it into the equation for elastic energy. I was just wondering why another method wouldn't work.
I tried doing it using the concept that Work is an equal to the Change in Elastic Energy, therefore Ee=xF...
Hi,
Could I please ask where I am going wrong with this very simple question:
Here's my answer (units implied):
A force of 20 extends the spring by 1/100 and so the Work Done in performing this extension is 20 * 1/100 = 1/ 5
Now, the work done in extending a spring is given by the formula...
This is purely for fun, as it won't affect my plot direction whatsoever.
Which of my scifi created humanoid races would you prefer to work with and why? Which would you not want to and why? Based on their behavior only?
Race 1: Take a positive view most all the time of situations, but can...
Hello I am new here lived in New York with my 2 kids and looking for a teaching job. I applied online but can't get response from them. I have received an email yesterday stated that they are going to give me an opportunity an engineering firm. They want me to fill a form with my all details...
The problem is based on a projectile-spring launcher. A ball is loaded into a tube that pushes back a spring and is then launched. The ball was launched straight horizontally not at an angle.
I'm trying to find the work done on the ball by the spring.
The info I have:
Displacement of spring =...
Hello,
I'm confusing about the basic terms about Conservation of Energy, Potential Energy and Work.
Consider that we have a mass ##M## above the ground (zero point) distance of ##y_{0}=h##. When we release the mass it will accelerate through it's way to ground. So the work is made by a field...
A box is moving at a constant velocity. 250N of applied force is acting on a box while 250N of friction is acting on it on the opposite direction. If the box travels 4 meters in the same direction as the applied force, how much work is done?
I know that work = force * displacement.
Is the...
I understand that work is done when (a) a force displaces an object, (b) energy is converted from one form to another, (c) heat is transferred between a system and its surroundings, yet I have trouble giving a precise definition for it.
Everywhere I go, the definition of energy is "the ability...
if I shoot the football, the ball will recive a force in specific direction, and it would follow that direction.
Does the work is done by me when I shooted the ball, or the ball does work when it moves all the period after my shooting ?
the work includes force and displacement , so who does the...
Buffer is a solution of weak acid and its conjugate base which resists the change in pH when strong acid/base is added to the solution.
But how does it work?
Consider,
HA + H2O ⇄ H3O+ + A-
When we add strong acid, the H+ from the strong acid reacts with the conjugate base A- to for HA...
My teacher told me that answers are F=1200 N for lifting straight up and F= 360 N for using the ramp. I can get the force for lifting straight up by using 1800=F(1.5)cos(0) but I do not understand why for using the ramp the equation 1800 = F(1.5)cos(72.5) does not produce the correct answer.
So I've been digging this problem for quite some time, and still can't figure out a way to obtain work done in AB.
I do understand that work done in AB = area under the graph. However, I can't figure out how to obtain the volume at B. I can't use PV=nRT since I am unable to obtain the...
I see physics problems asking one to calculate the work done in climbing stairs. However, isn't the system the person, and isn't the person not having any external work done? Then how can we say they did work?
Now I know when climbing or raising an object, work=mgh=potential energy.
But if the...
Attached is an example from my Tipler physics book of a determining the power delivered from a cars engine. I get the derivation(math), but am having some issues with the understanding/concept.
Mainly, isn't Power=Work done/time. If so, they define the system as Car-earth. There is no external...
Given: V_1 = 10 L, V_2 = 22 L
Not sure what I need to do here. We are told to ignore heat transfer, and the problem suggests that this is not a steady-state problem. The gage pressure is given, so I think that means we need to calculate for the absolute pressure, which would be 997 kPa. Cp and...
Hi All,
I understand carbon sequestration in the simplest sense is capturing and storing carbon.
As seen in the title, I'm going to split this into two sections.
i) How does it work?
I imagine that trees, in a sense are doing this. They take in the carbon from our atmosphere and is stored...
Fa = Force applied on the cart by the parent
Fax = x component For the force applied on the cart by the parent
Fay = y component For the force applied on the cart by the parent
Ff = force of friction
The method I thought to use was to solve for Facos, Fasin and then use pythagorean's theorem to...
I downloaded the amsmath package and am using the command \usepackage{amsmath} and its not working.
I have used it a few years ago, but can't remember whether I had this problem and what the solution was- I think it's something as simple as saving it in the right place if I recall quickly -...