Answer:
Dimension of cardboard is 22 m by 16 m
Explanation:
Given that,
Area = 352 cm²
Side of each square cutting from corner = 2 cm
Volume of box = 432 cm³
Let the two sides are x and y.
The area of the rectangular piece is
![xy=352](https://tex.z-dn.net/?f=xy%3D352)
-------- (1)
The volume of the rectangular piece
![2(x-4)(\dfrac{352}{x}-4)=432](https://tex.z-dn.net/?f=2%28x-4%29%28%5Cdfrac%7B352%7D%7Bx%7D-4%29%3D432)
![x^2-38x+352=0](https://tex.z-dn.net/?f=x%5E2-38x%2B352%3D0)
![(x-16)(x-22)=0](https://tex.z-dn.net/?f=%28x-16%29%28x-22%29%3D0)
x=16,22
Put the value of x in the equation (I)
For x = 16
For x = 22
Dimension of cardboard is 22 m by 16 m
Answer:
Current, I = 1000 A
Explanation:
It is given that,
Length of the copper wire, l = 7300 m
Resistance of copper line, R = 10 ohms
Magnetic field, B = 0.1 T
![\mu_o=4\pi \times 10^{-7}\ T-m/A](https://tex.z-dn.net/?f=%5Cmu_o%3D4%5Cpi%20%5Ctimes%2010%5E%7B-7%7D%5C%20T-m%2FA)
Resistivity, ![\rho=1.72\times 10^{-8}\ \Omega-m](https://tex.z-dn.net/?f=%5Crho%3D1.72%5Ctimes%2010%5E%7B-8%7D%5C%20%5COmega-m)
We need to find the current flowing the copper wire. Firstly, we need to find the radius of he power line using physical dimensions as :
![R=\rho \dfrac{l}{A}](https://tex.z-dn.net/?f=R%3D%5Crho%20%5Cdfrac%7Bl%7D%7BA%7D)
![R=\rho \dfrac{l}{\pi r^2}](https://tex.z-dn.net/?f=R%3D%5Crho%20%5Cdfrac%7Bl%7D%7B%5Cpi%20r%5E2%7D)
![r=\sqrt{\dfrac{\rho l}{R\pi}}](https://tex.z-dn.net/?f=r%3D%5Csqrt%7B%5Cdfrac%7B%5Crho%20l%7D%7BR%5Cpi%7D%7D)
![r=\sqrt{\dfrac{1.72\times 10^{-8}\times 7300}{10\pi}}](https://tex.z-dn.net/?f=r%3D%5Csqrt%7B%5Cdfrac%7B1.72%5Ctimes%2010%5E%7B-8%7D%5Ctimes%207300%7D%7B10%5Cpi%7D%7D)
r = 0.00199 m
or
![r=1.99\times 10^{-3}\ m=2\times 10^{-3}\ m](https://tex.z-dn.net/?f=r%3D1.99%5Ctimes%2010%5E%7B-3%7D%5C%20m%3D2%5Ctimes%2010%5E%7B-3%7D%5C%20m)
The magnetic field on a current carrying wire is given by :
![B=\dfrac{\mu_o I}{2\pi r}](https://tex.z-dn.net/?f=B%3D%5Cdfrac%7B%5Cmu_o%20I%7D%7B2%5Cpi%20r%7D)
![I=\dfrac{2\pi rB}{\mu_o}](https://tex.z-dn.net/?f=I%3D%5Cdfrac%7B2%5Cpi%20rB%7D%7B%5Cmu_o%7D)
![I=\dfrac{2\pi \times 0.1\times 2\times 10^{-3}}{4\pi \times 10^{-7}}](https://tex.z-dn.net/?f=I%3D%5Cdfrac%7B2%5Cpi%20%5Ctimes%200.1%5Ctimes%202%5Ctimes%2010%5E%7B-3%7D%7D%7B4%5Cpi%20%5Ctimes%2010%5E%7B-7%7D%7D)
I = 1000 A
So, the current of 1000 A is flowing through the copper wire. Hence, this is the required solution.
Reflection: a change in direction of a wave at a boundary between two different media.
sentence: i saw my reflection in the mirror.
refraction: the bending of light as it passes from one transparent substance into another.
sentence: when light goes through glass, it’s a refraction.
diffraction: the bending of waves around the corners of an obstacle.
sentence: spaced tracks on a CD act as a diffraction.
absorption: the process or action by which one thing absorbs or is absorbed by another.
sentence: heat waves hitting the beach usually give most of their energy to the sand.
interference: when two waves lay on each other and their energies are either added together or cancelled out.
sentence: interference waves can be observed with all types of waves.
standing wave: two waves moving in opposite directions. they both have the same amplitude or frequency.
sentence: plucking the string of a guitar is an example of standing waves.
resonance: increased amplitude that occurs when the frequency of a force is equal or close to a natural frequency.
sentence:a buzz in your car that only occurs at a certain speed is an example or resonance.
<span>the ratio of the velocity of light in the medium over the velocity of light in a vacuum</span>
Answer:
C
Explanation:
Static electricity is what makes your hair stand up when you rub a balloon against it or gives you a shock from your doorknob. In static electricity, electrons are moved around mechanically (i.e. by someone rubbing two things together).
HOPE THIS HELPED AND LETTER D MADE ME LAUGH