I suspect that they operate on the basic Faraday Law principle, with perhaps some imbellishments. The basic principle is inducing eddy currents in metallic objects, especially good conductors, so in this case being magnetic contributes only slightly. The best conductor per unit weight is aluminum. The loop may look for de"Q"-ing or for frequency shifts (i.e., like a good metal detector) resulting from the presence of the metal object. Next time you go through Airport Security, ask them how their system works.MATLABdude said:Wait a second, it just occurred to me: wouldn't the metal have to be in motion in order to induce any current in the loop?! Wait, they've probably got a current going in the loop, and looking to see how much of it gets coupled out to any metallic objects around.
There are a few ways to trigger a traffic light on a bicycle. The most common method is to use a bike-specific traffic light trigger, which is usually a small button or sensor that you can press or ride over to activate the traffic light. Some cities also have special bike lanes with induction loops that can detect bicycles and trigger the traffic light. Alternatively, you can wait for a car to pull up behind you and trigger the light, or dismount and press the pedestrian crossing button.
Some traffic lights are not equipped with sensors that can detect bicycles, so they will not change unless triggered by a car or pedestrian. Additionally, if you are not positioned in the right place or do not have enough metal in your bike to trigger the induction loops, the light may not change for you. It is important to familiarize yourself with the traffic lights in your area and know where the trigger points are located.
Yes, you can trigger a traffic light on your bicycle without stopping if you have a bike-specific traffic light trigger or ride over an induction loop. However, it is important to follow traffic laws and signals, so if the light does not change for you, it is best to wait and follow the rules of the road.
No, not all cities have bike-friendly traffic lights. It ultimately depends on the infrastructure and resources of the city. Some cities may have dedicated bike lanes and traffic light sensors, while others may not have any accommodations for bicycles. It is important to research and familiarize yourself with the traffic laws and signals in the cities you plan to ride in.
Yes, there are a few safety precautions to keep in mind when triggering a traffic light on your bicycle. Make sure to always follow traffic laws and signals, and be aware of your surroundings. Look out for cars and pedestrians, especially if you have to dismount or stop to trigger the light. It is also important to properly signal your intention to turn or cross the intersection. Additionally, make sure to position yourself in the designated bike lane or area to ensure the traffic light can detect you.