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Physics
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26 Nov 2019

A statement found to be experimentally valid over a wide range ofobserved phenomena is referred to as a

a. model.
b. principle.
c. theory.
d. hypothesis.
e. law.

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Patrina Schowalter
Patrina SchowalterLv2
19 Jun 2019
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Related textbook solutions

Physics: Principles with Applications
7th Edition, 2013
Giancoli
ISBN: 9780321625922

Related questions

True/False?
1. Ohm's Law isvalid when for a given piece of material theratio V/I is the samefor a wide range of voltages andcurrents.
2. For anOhmic conducting material the resistivity depends onthe electricfield and the current density.
3. Acurrent of 0.5 A exists in a 60-Ohm lamp. The appliedpotentialdifference is 30V.
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Curious about the resistance of an audio speaker, Luke KlausLeemeasures the
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Luke measures the voltage of a D cell battery to be 1.45 V.Heconnects this to the
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Assume that the rated impedance has about one significant digit(6means between 5.5
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(b) What is the range of possible values for the inductance ofthespeaker coil if the
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Imagine you are looking down from a great height onto a pool ofcross sectional area A. Throughout the water are suspended N blackballs of cross section sigma.

a) Find the expected fraction of the bottom of the pool you cansee, as a function of the number N of balls in the pool.

b) Now let the ball sizes be distributed as a power-law in sigmaover some wide range of sigma. Find the value of that power suchthat the small balls are just as important for blocking the pool asis the large balls.


Here's what I've got
For part a:
I assume the pool is round (can I make this assumption?)
Let N = total number of balls
Let R = radius of pool
Let A = cross-sectional area of pool = 4piR^2
Let r = radius of one ball
let a = cross-sectional area of one ball = 4pir^2

Then the total cross-sectional area occupied by all the balls is =Na = N(4pir^2)
Then the area of the pool that can be seen is =
[A - Na]/A = [(4piR^2) - N(4pir^2)]/(4piR^2) = 1 -[N(r^2)]/R^2
I believe this is correct for part a.

For part b I have no idea how to do a power-law so if you couldshow as many details as possible I would appreciate it.

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