Learn about the various ways electricity can travel that could potentially be hazardous or unsafe. Using Scratch, a free computer coding platform for students, code a safety message to help teach others to stay safe.
Power lines are conductive meaning the electrical current runs through them with the least resistance. However if something makes contact with a live power line like a tree, kite, or ladder, the electrical current may flow to the ground. The place where the current touches the ground is the highest voltage and from that point the electrical current spreads out in irregular concentric circles. The voltage or electrical intensity decreases as it moves further from the source. 10 metres or more from the source of contact, like a downed power line, is a safe distance.
Touch potential is the ability electricity has to find its way through touch to get to the ground. If a kite gets tangled in a power line, the electrical current could travel through the kite and you to reach the ground. Birds do not get zapped when standing on a power line, however they would if they straddled two power lines, or touch their beak to the ground while standing on the power line.
Step potential is the ability electricity has to move through your body as you step away from the source of electricity. As electrical current flows through the ground the voltage decreases in concentric rings or ripples as you move further from the source. However, if you move away by lifting one foot, the change in voltage between the concentric rings can travel up one leg and down the other. Instead by keeping your legs together and shuffling your feet, the electrical current will stay in the ground. 10 metres is the safe distance calculated based on the voltage in the power lines here in B.C.
Arcing is the ability electricity has to jump through the air to find a path to ground. The term arcing describes the shape the electrical current uses to get to the ground. Some jobs around your home may take you close to power lines, such as trimming trees, working on your roof, or doing exterior renovations. It is important to keep yourself and any tools you’re using at least three metres (the length of a four-door car) away from power lines near your home. This is because electricity can "arc" or jump from power lines across a gap, to tools or ladders that you're using.
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