Oh really? potential difference sucks

In summary, the potential difference of 6 volts is needed to transfer 0.19 coulombs of charge and for an electron to achieve a speed of 6% of the speed of light starting from rest, a potential difference of 1.79875e8 volts is required. These calculations were determined using the equations W=qV and V=PE/q.
  • #1
smd1991
3
0
1) You have a potential difference of 6 volts. How much work is done to transfer .19 coulombs of charge through it? Answer in units of Jules.

2) Through what potential difference would an electron need to be accelerated for it to achieve a speed of 6% of the speed of light(2.99792e8), starting from rest? Answer in units of Volts.

W=Fd=qEd
PE=-W=-qEd
Potential difference between two points is V=PE/q

q=charge in coulombs.
w=work
PE=potential energy
d=distance
E=field
v=potential difference
 

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  • #2
I can't see the attachment yet, but for (1), you can use W=qV.

Now, (2) should be clear.
 
  • #3


1) To find the work done, we use the formula W=qEd. Plugging in the given values, we get W=(0.19 C)(6 V)=1.14 Jules. Therefore, 1.14 Jules of work is done to transfer 0.19 coulombs of charge through a potential difference of 6 volts.

2) To find the potential difference needed to accelerate an electron to 6% of the speed of light, we use the formula V=PE/q. We know that the potential energy (PE) of an electron is equal to its kinetic energy (KE) when it is moving at a certain speed. So, we can set PE=KE and solve for V. We know that KE=1/2mv^2 and we are given the mass of an electron (m) and the desired velocity (0.06c). Plugging in these values, we get KE=0.5(9.10938e-31 kg)(0.06*2.99792e8 m/s)^2=1.097e-14 J. Since PE=KE, we can set V=PE/q and solve for V. Plugging in the calculated PE and the charge of an electron (q=1.60218e-19 C), we get V=(1.097e-14 J)/(1.60218e-19 C)=6.85e5 Volts. Therefore, the potential difference needed to accelerate an electron to 6% of the speed of light is 6.85e5 Volts.
 

Related to Oh really? potential difference sucks

1. What is potential difference?

Potential difference, also known as voltage, is the difference in electric potential between two points in an electrical circuit.

2. Why does potential difference matter?

Potential difference is important because it is what drives the flow of electric current in a circuit. Without a potential difference, there would be no movement of electrons and no electricity.

3. How is potential difference measured?

Potential difference is typically measured using a voltmeter, which is connected in parallel to the two points in the circuit where the potential difference is being measured. The unit of measurement for potential difference is volts (V).

4. What factors affect potential difference?

The main factors that affect potential difference are the amount of charge and the distance between the two points in the circuit. The greater the charge and the closer the points are, the higher the potential difference will be.

5. Can potential difference be negative?

Yes, potential difference can be negative if the electric potential at the second point is lower than the first point. This can happen in circuits with certain types of components, such as batteries and diodes, which can generate a reverse potential difference.

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