Answer:
Work = F * s where s is the distance F moves
Since F is stationary, in this case, "no work" is done by either person
The electron is accelerated through a potential difference of
![\Delta V=780 V](https://tex.z-dn.net/?f=%5CDelta%20V%3D780%20V)
, so the kinetic energy gained by the electron is equal to its variation of electrical potential energy:
![\frac{1}{2}mv^2 = e \Delta V](https://tex.z-dn.net/?f=%20%5Cfrac%7B1%7D%7B2%7Dmv%5E2%20%3D%20%20e%20%5CDelta%20V%20)
where
m is the electron mass
v is the final speed of the electron
e is the electron charge
![\Delta V](https://tex.z-dn.net/?f=%5CDelta%20V)
is the potential difference
Re-arranging this equation, we can find the speed of the electron before entering the magnetic field:
![v= \sqrt{ \frac{2 e \Delta V}{m} } = \sqrt{ \frac{2(1.6 \cdot 10^{-19}C)(780 V)}{9.1 \cdot 10^{-31} kg} }=1.66 \cdot 10^7 m/s](https://tex.z-dn.net/?f=v%3D%20%5Csqrt%7B%20%5Cfrac%7B2%20e%20%5CDelta%20V%7D%7Bm%7D%20%7D%20%3D%20%5Csqrt%7B%20%5Cfrac%7B2%281.6%20%5Ccdot%2010%5E%7B-19%7DC%29%28780%20V%29%7D%7B9.1%20%5Ccdot%2010%5E%7B-31%7D%20kg%7D%20%7D%3D1.66%20%5Ccdot%2010%5E7%20m%2Fs%20)
Now the electron enters the magnetic field. The Lorentz force provides the centripetal force that keeps the electron in circular orbit:
![evB=m \frac{v^2}{r}](https://tex.z-dn.net/?f=evB%3Dm%20%5Cfrac%7Bv%5E2%7D%7Br%7D%20)
where B is the intensity of the magnetic field and r is the orbital radius. Since the radius is r=25 cm=0.25 m, we can re-arrange this equation to find B:
Answer:
t = 2.2 s
Explanation:
Given that,
A person observes a firework display for A safe distance of 0.750 km.
d = 750 m
The speed of sound in air, v = 340 m/s
We need to find the between the person see and hear a firework explosion. let it is t. So, using the formula of speed.
![v=\dfrac{d}{t}\\\\t=\dfrac{d}{v}\\\\t=\dfrac{750\ m}{340\ m/s}\\\\t=2.2\ s](https://tex.z-dn.net/?f=v%3D%5Cdfrac%7Bd%7D%7Bt%7D%5C%5C%5C%5Ct%3D%5Cdfrac%7Bd%7D%7Bv%7D%5C%5C%5C%5Ct%3D%5Cdfrac%7B750%5C%20m%7D%7B340%5C%20m%2Fs%7D%5C%5C%5C%5Ct%3D2.2%5C%20s)
So, the required time is 2.2 seconds.
Answer:
Roles and responsibilities
Explanation:
Definition of safety plan:
"A Safety Plan is a written document that describes the process for identifying the physical and health hazards that could harm workers, <em>procedures to prevent accidents</em>, and steps to take when accidents occur. Written safety plans can be comprehensive, such as an injury and illness prevention program, or they can be specific to a particular activity, hazard, or piece of equipment. The written safety plan is your blueprint for keeping workers safe."
Alternative definition
"What is an OSHA Safety Plan? An OSHA Safety Plan is a written plan that describes the potential hazards in the workplace, <u><em>and the company policies</em></u>, controls, and <u><em>work practices</em></u> used to minimize those hazards."
elements of a safety plan:
Basic Safety Plan Elements
Policy or goals statement
<u><em>List of responsible persons</em></u>
Hazard identification
<em>Hazard controls and safe practices</em>
<em>Emergency and accident response</em>
Employee training and communication
<em>Recordkeeping</em>
I say roles and responsibilities because it makes sense that if it's your responsibility and possibly something that could be dangerous -- hence a safety plan -- you would have to sign it before working. I hope this helps!
The answer is definitely C.) their molecules move at the same average speed