Static Electricity: Reduce Shock by Holding a Doorknob

In summary: By grounding herself, she can reduce the potential difference between the two of you, making the shock less severe. It's not a perfect solution, but it can help.
  • #1
lisamay44
7
0
You rub your feet on the carpet in your warm living room on a cold winter day. You know you have gained static electrical charge on your body. You decide to touch your sister to shock her. Your sister knows that in order to reduce the electrical shock she will feel when you touch her, she
(A)must stand very still
(B) hold on to a doorknob
(C)jump up and down at exactly 60 Hertz
(D)rub her feet on the carpet

I have narrowed this down to answers B and D. I am leaning toward answer B, because if the sister rubs her feet on the carpet, as in answer D, there still might be a charge differential between the two people and therefore there would still be a shock. I think, but am not sure, that B would "ground" the charge. Please help!
 
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  • #2
If (B) would ground her, she would still get a shock, right? As would you, so that might be ok. Suppose she could charge herself up to the same potential as you? Then what would happen? How might she do this? I think you know the correct answer.
 
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  • #3
I'm just confused because even if she rubs her feet on the carpet, there is no guarantee that she will charge herself to the same potential as you.

On a related note, when you ground yourself you produce an electric shock? Does this occur because you are transferring a charge back to the earth?
 
  • #4
Nope, no guarantee. But the less the potential difference, the less the shock. Shocks are mutual, the same current passes through both parties. The trick to shocking someone is that you expect it and they don't. It's largely psychological. Grounding one doesn't make much difference.
 
  • #5
lisamay44 said:
I'm just confused because even if she rubs her feet on the carpet, there is no guarantee that she will charge herself to the same potential as you.

True, but your original question said "reduce" not eliminate.
 

1. What is static electricity and how is it created?

Static electricity is a build-up of electric charge on the surface of an object. It is created when certain materials, such as rubber or wool, rub against each other and electrons transfer from one material to another. This creates an imbalance of positive and negative charges, resulting in static electricity.

2. Why do we experience shocks when touching a doorknob?

When you walk across a carpeted floor, your body picks up extra electrons from the carpet, giving you a negative charge. As you reach for a doorknob, which is usually made of metal, the electrons from your body are attracted to the positively charged doorknob, resulting in a static shock.

3. How can holding a doorknob help reduce static shock?

Holding a doorknob can help reduce static shock because it allows the static electricity to flow from your body to the doorknob, instead of building up and causing a shock when you touch the doorknob. This allows for a more gradual discharge of the static electricity, reducing the intensity of the shock.

4. What are some other ways to prevent or reduce static shock?

Some other ways to prevent or reduce static shock include wearing shoes with rubber soles, using a humidifier to add moisture to the air, and avoiding wearing clothes made of materials that are prone to creating static electricity, such as wool or synthetic fabrics.

5. Is static electricity harmful to our health?

Most static shocks are harmless and do not pose a health risk. However, in rare cases, static electricity can cause ignition of flammable gases or liquids, so it is important to avoid generating static electricity in environments where this could be dangerous, such as near gasoline pumps or chemical storage areas.

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