A. person leans on/pushes a brick wall
b. walking in sand
c. turning on a fan
D. person running into a wall
Answer:
![V =-7221.43 \ V](https://tex.z-dn.net/?f=V%20%3D-7221.43%20%5C%20V)
Explanation:
<u>The Electric Potential</u>
The electric potential at a point is equal to the electric potential energy (measured in joules) of any charged particle at that location divided by the charge (measured in coulombs) of the particle.
To calculate the electric potential of a point charge Q at a distance r, we use the formula:
![\displaystyle V=\frac{kQ}{r}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20V%3D%5Cfrac%7BkQ%7D%7Br%7D)
Where
![k=9\cdot 10^9\ N.m^2/c^2](https://tex.z-dn.net/?f=k%3D9%5Ccdot%2010%5E9%5C%20N.m%5E2%2Fc%5E2)
We are given the following data:
![Q=-3.37\cdot 10^{-6}\ c](https://tex.z-dn.net/?f=Q%3D-3.37%5Ccdot%2010%5E%7B-6%7D%5C%20c)
r = 4.20 m
Calculating:
![\displaystyle V=\frac{9\cdot 10^9*(-3.37\cdot 10^{-6})}{4.2}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20V%3D%5Cfrac%7B9%5Ccdot%2010%5E9%2A%28-3.37%5Ccdot%2010%5E%7B-6%7D%29%7D%7B4.2%7D)
![\mathbf{V =-7221.43 \ V}](https://tex.z-dn.net/?f=%5Cmathbf%7BV%20%3D-7221.43%20%5C%20V%7D)
Answer:
Radioactive therapy
Explanation:
Radioactive materials were believed to have medicinal properties like having antibacterial effect and ability to cure a wide range of ailment. Radioactive therapy was marketed with the idea that humans had a high tolerance level for the radioactivity. It was not until research showed that the tolerance level was very much lower than thought, and the lethal side effects of radioactivity understood, that radioactivity was seen as highly dangerous, and handled with extreme caution and precautions.
Answer:
c. clockwise
Explanation:
This is because, the magnetic field, B produced due to the downward flowing current in the straight wire is perpendicular to the plane of the rectangular conducting loop and directed outwards from it.
Since it also decreases as it goes from the top of the loop to the bottom of the loop (and also from left to right since B ∝ 1/r), there is a change in magnetic flux which is negative, and thus and induced emf or current is generated to oppose this change in magnetic flux which is generating the current according to Lenz's law. To generate a magnetic field in the opposite direction to that due to the straight wire, a current flowing in the clockwise direction must be generated in the loop.
So the answer is C. clockwise.