What happens if you bring two iron nails close to or touching each other? Take turns rotating the cord and checking the galvanometer, even jumping in for fun during the activity. Identify and describe the basic parts of the generator model shown in the figure below. In some metal detectors, it is the device that is moved over the object. The metal in the cookware has electrical resistance that opposes the induced current and causes friction for the pot to heat up. Disassemble the set up when making the needed shape adjustments and sanding of the copper wire. Place the different magnets and electromagnets under the improvised magnetic board one at a time.
Test for the presence of magnetism again. The direct current in the coil is supplied via two brushes. Philippines: Pearson Education Asia Pte. Together, when used, will make the magnetic field surrounding the latch magnets visible. Using arrows, draw the magnetic compass needle directions at the indicated locations in Figure 11b.
Check that the bottom ends of the wire curl loosely around the magnets forming a closed circuit. Formulated the principle behind electromagnetic induction. Lightly drag the top latch magnet obliquely over the other, and at an angle to the horizontal. Answer the following question briefly but substantially. Lift the magnet off the test tube and repeat with ten or more strokes. A changing magnetic field produces an electric field and a changing electric field produces a magnetic field. Using the right-hand rule, the direction of this force is in the direction where the palm faces.
Use the galvanometer with care so as not to drop it. Diagnosis of bone fractures 4. Steady magnetic lines of induction surround a battery-powered electromagnetic nail. What other observations have you made regarding your electric motor model? If we were to increase the number of coils the strength of the magnetic field would increase, also increasing the strength of the magnet. Assembly of the Electric Motor Model — Cut the length of copper wire into three pieces.
Use Table 3 and extend your understanding of the recording industry by matching the devices in Column B and their respective functions in Column C with the items in Column A. How many of the devices you identified inside the control room need electricity to operate? A quicker way to know the polarity of a permanent or induced magnet is by the use of a magnetic compass which you will be using in the next set of activities. Complete the following statement: A metallic detector was used to check a bag for metallic objects. The alternating current sent through the buried coils produce an electromagnetic field in each coil. The principle of electromagnetic induction in two nearby coils can be demonstrated by a transformer. How does an electric generator work? There is a uniform magnetic field around the coil.
If a cellular phone or any gadget with built in camera is available, take pictures of the magnetic compass needle orientations for different locations around the bar magnet. Electric bells also contain an electromagnet. Practical work in high school physics -Asourcebook for teachers. Both the electric field and the magnetic field oscillate perpendicular to each other and to the direction of the propagating wave. On the wooden block, position the magnetic compass right next to the vertical wire in four equidistant locations relative to the north-south alignment. The magnetic field gets stronger with increasing distance from the wire.
People readily adopt emerging technologies. In set up B, the magnet is being pulled out of the moving coil with the same speed. Pull the magnet out of the coil. . Olarte, Jane Chavarria, Nilo G. Vehicles driven over the buried coils activate a traffic light sensor. Pasig City: Cengage Learning Asia Pte.
Use an improvised magnetic board and a pair of latch or refrigerator magnets similar to those shown below to observe magnetic field lines. This wire is connected to an electrical power source and a meter. Set up the galvanometer, wooden blocks and bar magnets as shown in Figure 19. Typical red-light traffic systems have two induction-loop triggers made of rectangular or concentric wire loops buried under the road close to the stop line. The magnetic field is strongest inside the current-carrying coil. Extending Inquiry of Model — Tinker with your electric motor model and try to look for other ways to demonstrate the same effect by an electromagnetic force.
The hammer hits the gong and it makes a sound. The magnet produces a clockwise current in the coil. University of the Philippines - National Institute for Science and Mathematics Education Development. The magnetic field vary directly with the distance from the coil. Extension Question: What will happen to a magnet if it is dropped too often? The activity on the jump wire generator operates using the principles of electromagnetic induction. Published by the Department of Education Secretary: Br. Shaking the Iron Filings inside the Test Tube Guide Questions: Q19.