Electricity Sparks: Finding the Voltage Difference for a 0.2 cm Jump

In summary, the conversation involves determining the minimum voltage difference between a finger and a doorknob for a spark to occur. The formula V=Ed is used, but the incorrect value for E is initially plugged in. After realizing the mistake, the correct value of E is used to calculate the voltage difference.
  • #1
whoknows12345
9
0
Suppose that after walking across a carpeted floor you reach for a doorknob, and just before you touch it a spark jumps 0.2 cm between your finger and the doorknob. Find the minimum voltage difference betwen your finger and the doorknob for this to occur.

I did V=Ed

which I plugged in (8.85 x 10^-12)(.2 x 10^-3) and I got this wrong. What am I doing wrong?
 
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  • #2
whoknows12345 said:
Suppose that after walking across a carpeted floor you reach for a doorknob, and just before you touch it a spark jumps 0.2 cm between your finger and the doorknob. Find the minimum voltage difference betwen your finger and the doorknob for this to occur.

I did V=Ed

which I plugged in (8.85 x 10^-12)(.2 x 10^-3) and I got this wrong. What am I doing wrong?
How are you determining what E is? It seems to be several orders of magnitude out. I think the breakdown E for air is in the order of a few million volts/metre. Also you appear to be using .2 mm not .2 cm.

AM
 
  • #3
so it would be ((8.85 x 10^-12)/1.00059) x (2.2 x 10^-2) which is 1.769e-14?
 
  • #4
nevermind, i got it. i was using the wrong E, E was 3,000,000
 

1. How do electricity sparks occur?

Electricity sparks occur when there is a sudden flow of electric current through a gap in the air or another insulating material, causing a visible flash or spark.

2. What is the voltage difference for a 0.2 cm jump?

The voltage difference for a 0.2 cm jump can vary depending on the conditions, but is typically around 10,000 volts.

3. How is the voltage difference for a 0.2 cm jump measured?

The voltage difference for a 0.2 cm jump can be measured using a voltmeter, which is a device that measures electrical potential difference between two points in an electrical circuit.

4. What factors affect the voltage difference for a 0.2 cm jump?

The voltage difference for a 0.2 cm jump can be affected by the material of the electrodes, the distance between the electrodes, and the surrounding air pressure and humidity.

5. Why is it important to find the voltage difference for a 0.2 cm jump?

Knowing the voltage difference for a 0.2 cm jump can help us understand and control the behavior of electricity and prevent accidents or damage caused by high voltage sparks.

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