03 Feb Why is electric shock dangerous?
All of us, at some point of time in life, got electric shock due to careless attitude. One has to be very careful of electric shocks and elder persons always warn children to be careful while handling electrical devices. Small children are even advised not to touch electrical instruments. Do you know thousands of people die of electric shock all over the world every year? This shows that great caution is necessary in the use of electric appliances. It is therefore imperative that we understand the basic principles of electricity. You physics tuition will just do that for you. In today’s physics tuition, you will learn why electric shock is dangerous.
Electricity flows or gets conducted through metals such as silver, copper, aluminium or iron more easily. They are called good conductors of electricity. Wood, air, glass, rubber, porcelain, etc. offer great resistance to its flow. They are called insulators and are usually used for confinement of electricity within the conductors. You can see these insulators easily covering the flexible cord that is used to make the connections in the home electrical devices to the plug them to the switchboard. Due to wear and tear, the insulation deteriorates and can crack or peel off. Such a defective flexible cord is dangerous and you can get an electric shock if you touch it. So such a defective cord should be immediately changed. Remember to use only the cords having three wires, thus having a good quality earth connection. This third wire is meant to conduct the leakage of the current to the earth. There will be always a high percentage of risk involved without this earth connection and you may get an electric shock. Do you know how why we actually get an electric shock?
In fact, when our body is dry it presents considerable resistance against electric current, but in case of wet bodies this resistance falls. Dry skin offers 100 to 600 times more resistant than the wet skin. At times when we are standing on insulations such as rubber or wood, a very small amount of current can flow through our body. But, in case we are wet or standing on wet ground, as in a bathroom, a bigger amount of current will be able to pass through our body resulting in an electric shock.
The current flow rate through the body determines the severity of an electric shock. In the case when only about 0.1 ampere current flows through any major organ of our body, such as the heart, it can be dangerous. Obviously the electric shock is more dangerous with a bigger amount of electric current and duration of such current flow.
We hope you enjoyed this lesson from physics tuition. We will be back with more such interesting findings in our next physics tuition.