Electical shock, electrocution questions

In summary, the first question concerns getting shocked by spark plug leads on small engines and cars. The voltage is high, but the current is low, so it is not life threatening. However, even if your body is not completing a circuit, you can still get shocked due to the low resistance of air compared to your body. The second question is about introducing household AC power into a swimming pool and whether a person swimming in the water could be electrocuted. It is possible if there is a drain and the ground of the radio is well insulated, but the circuit breaker would not be thrown.
  • #1
johnl
11
0
HI, I couldn't decide which forum was the best to post these in. I have two questions regarding electricity and getting shocked, or electrocuted.

1. Being shocked from the spark plug leads on either small engines (lawnmowers) or cars. Classically, on either of these, you have a coil which acts as a transformer to kick the voltage up to approximately 10,000 to 20,000 volts needed to force a spark to jump the sparkplug gap. THe current is relativley small. Touching the spark plug leads while this voltage is present will give you a good jolt, but is far from life threatening, I assume because the current is low. My question is, if you only contact the voltage at one point on your body, ie hand, are wearing shoes with thick soles, have no part of your body completing a circuit back to ground at the car or engine, (your body is not completing a circuit) then why do you get shocked?

2. Household AC power , say 110volts. Say you introduce this into a swimming pool of water (10 feet deep) that someone is swimming in by dropping a radio or other appliance into the water that is on and plugged into a household outlet. Say the person is 6 or 7 feet from the radio in the water, and the water contains enough minerals to conduct electricity to some degree. Assume the person is not touching anything but water. I don't see why the person would be electrocuted, because I can't see how they complete a circuit for the electricity. I would think it would seek ground via the radio itself and throw the breaker at the house. That being said I have no intention of conducting such an experiment on myself or anyone else for that matter lol.

John
 
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  • #2
1) I'm not sure if this is the best answer, but air is a much better insulator than your body and your hand, so even a convoluted route through you and back out the other half of your finger will have less resistance than a path through only the air.

2) If there is a drain in this pool, and the ground of the radio is well insulated, then you would have a voltage difference between the drain and the radio, but the circuit breaker wouldn't be thrown. If there is enough chlorine in the pool to make its resistance low enough, and you just happen to be between the radio and the drain, you could be electrocuted.
 
  • #3
,

I can provide some insight into your questions about electrical shock and electrocution.

1. The reason you get shocked when touching the spark plug leads on a small engine or car is because your body is completing the circuit. Even if you are only touching the voltage at one point on your body, the electricity will still flow through you and back to the ground through the engine or car. Your body may have a higher resistance than the metal parts of the engine, but it is still enough to allow the current to flow and give you a shock. The reason the shock is not life-threatening is because the current is relatively low and the duration of the shock is short. It is important to always use caution when working with electrical equipment to avoid serious injury.

2. In the scenario you described, the person in the swimming pool could potentially be electrocuted if the radio or appliance was not properly grounded and the person became part of the circuit. Water is a good conductor of electricity, so even though the person may not be touching anything else, the electricity could still pass through their body and cause harm. It is important to always make sure that electrical appliances are properly grounded and to never use them near water.

Overall, it is important to remember that electricity is a powerful and potentially dangerous force. It is always best to take precautions and use proper safety measures when working with electricity to avoid any accidents or injuries.
 

Related to Electical shock, electrocution questions

1. What is an electrical shock?

An electrical shock occurs when a person comes into contact with an electrical energy source. This can happen through direct contact with a live wire or through contact with an object that is energized by electricity. The severity of an electrical shock depends on the amount of current flowing through the body and the duration of the shock.

2. What is the difference between an electrical shock and electrocution?

An electrical shock refers to the physical sensation a person experiences when coming into contact with electricity, while electrocution refers to death caused by an electrical shock. Electrocution occurs when the electrical shock is severe enough to disrupt the heart's rhythm, leading to cardiac arrest.

3. What are the common causes of electrical shocks?

Electrical shocks can be caused by a variety of factors, including faulty wiring, damaged electrical appliances or cords, and coming into contact with power lines. Accidental contact with electrical outlets, switches, or exposed wires can also result in shocks.

4. What are the symptoms of an electrical shock?

The symptoms of an electrical shock may vary depending on the severity of the shock and the amount of current flowing through the body. Common symptoms include a tingling or burning sensation, muscle contractions, numbness, difficulty breathing, and potentially loss of consciousness.

5. How can I prevent electrical shocks?

To prevent electrical shocks, it is important to always follow safety precautions when working with electricity. This includes turning off the power before making any repairs or adjustments, using insulated tools, and wearing protective gear. It is also important to regularly check and maintain electrical appliances and wiring to ensure they are in good working condition.

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