All Questions
Tagged with potential-energy homework-and-exercises
394
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From my reference frame, why does the Earth need a huge kinetic energy [$0.5M_E(11200)^2=3.75*10^{32}$ joules] to escape me? [closed]
I wake up screaming into the void, when I see the Earth almost touching me but going away from me at 11.2 $km/s$.
I don't remember what happened before I woke up. I faintly recollect being cannoned up ...
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Gravitational Potential Energy Lab Confusion
I had a lab that tested the dependence of gravitational potential energy on its position and the goal out of each exercise was to see if kinetic energy equaled potential energy. A cart was on a flat ...
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Textbook question on calculation of potential difference between two points
My textbook has the following question
What is the potential difference between two points that are 50cm and 80cm respectively from a point charge of 2uC?
Unfortunately, the textbook has not taught ...
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2
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Deriving gravitational potential energy using vectors
Here is my attempt at derivation:
First you must find a vector function for the gravitational force.
By the inverse square law, the magnitude of gravitational force between two bodies of mass $m$ ...
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1
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What are the points to note in a spring+block system? [closed]
This is the solution to a question related to spring+block system, and I have some doubts regarding the concept behind this question
The solution reads
The velocity of the block increases till the ...
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2
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Electrostatic energy of "a spherical dielectric shell and a point charge at the center"
The inner radius of the dielectric shell is $a$, and the outer radius is $b$. I tried to use the formula involving the square of the electric field, and found $E$ in three regions. But when I evaluate ...
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Energy of a spherical shell
System: spherical shell with surface density.
Objective: calculate potential energy.
I found energy through potential.
Next, I found the formula for energy through the field, which gives two ...
- 206k
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Deriving expression for gravitational potential energy around a mass, $M$, using vectors
(I think my question will be somewhat related to this one: Deriving gravitational potential energy using vectors .)
I know the change in the potential energy associated with a conservative force, $\...
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Question about Problem $12$ in Chapter $11$ from Kibble & Berkshire's book
I write again the problem for convinience:
A rigid rod of length $2a$ is suspended by two light, inextensible strings of length $l$ joining its ends to supports also a distance $2a$ apart and level ...
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Hanging mass from spring/ Setting potential to 0
I'm working a problem from Taylor's Classical Mechanics Book, and it's highlighted a couple issues I never quite wrapped my head around (despite getting good marks in advanced undergrad mechanics and ...
CommunityBot
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Why can we ignore the work done by gravity?
I am working through the problem above, starting with part (d). By the conservation of energy setting the spring in equilibrium as $y_0$ as the difference in length of the unstretched spring to the ...
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How do I find the energy difference between two points of a gravitational gradient?
What I'm ultimately trying to figure out is how to calculate only the potential energy attributed to the differences in the force of gravity at two distances from the Earth's center of gravity.
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What happens when a voltmeter is connected across two parallel circuits?
Edit: Link to question.
I'm looking at question 4.6. I cannot understand how to make sense of this arrangement of voltmeter, let alone answer the question. Any help is very much appreciated.
Are you ...
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Lagrangian function of a mass-spring-system with deflections in 2D [closed]
I’m looking for the lagrangian function of the following problem (as seen in the picture). We have a mass connected to two springs. We can deglect the mass in two dimensions.
My main problems are:
...
CommunityBot
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Gravitational potential energy of an isothermal sphere
I am trying to calculate the gravitational potential energy, W, defined as:
$$W = -\frac{1}{2}\int\rho(r)\Phi(r)\mathrm d^{3}r$$
for an isothermal sphere. I am given that the density profile varies ...
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