Lab 5: Magnetic Fields Online Version We will be using the PHeT Magnet and Compass simulation this week. You can find the simulation at: https://phet.colorado.edu/en/simulations/magnet-and-compass/about Introduction: Magnet and Compass To explore how the different options work in this simulation, which is set up a little differently than other simulations we've used so far, start by deselecting all options on the right menu except for the magnet. 1. What do you think the magnetic field produced by the magnet will look like? 2. Check your prediction by selecting the "show field" tab. Were you correct? 3. If you were to chop this magnet in half and separate the pieces, what would be the polarity of each piece? Why? 4. Select the "show inside magnet" tab. Do you still agree with your prediction from above? Why or why not? 5. Deselect the "Show Field" tab. Make a prediction: If you place a compass near the magnet, what will the compass do? Why? 6. Select "Show Compass." Move the compass to several positions around the magnet. What do you notice? 7. Select "show planet Earth." What do you notice? Are the North and South poles where you expect them to be? Why? 8. Move the compass to various positions around the Earth. This confirm your guess about how compasses work? Why or why not?

Part 1: Nature of Magnetic Fields Select the tabs "See Inside Magnet" and "Show Compass," make sure "Show Field" is turned off, and you should have a set-up like this: 1. Drag the compass around to the bar magnet. Watch the red arrow of the compass needle. What do you notice about the needle color as you drag it around the magnet? 2. Now click the Flip Polarity button and do the same thing. What do you notice about the needle? 3. Select the "Show Field" tab, take a screenshot, and place it here. Alternately, if you've printed out the write-up, sketch what the field looks like around the compass and magnet. 4. Draw a diagrammatic version of this field around the bar magnet below. Place arrows on the field going from North to South.

Part 2: Magnetic Field Strength Click on the "Field Meter," and focus only on top magnetic field strength value, ?. Place the "+" of the meter close to the South pole and take a reading, recording that reading in the Distance 1 column of the table below. Then drag the "+" from South to North approximately the same distant. Take a reading at four additional points from South to North and place in the column "Distance 1" in table 1 below: Magnetic Field (G) for 75% Bar Magnet Strength Distance 1 Distance 2 Distance 3 Point 1: South Point 2 Point 3 Point 4 Point 5: North Now do exactly the same thing, except pull the "+" of the Field Meter further away from the South pole and read five points approximately the same distance and place in "Distance 2." Repeat for a third time, pulling the Field Meter even further out and place at some "Distance 3." 1. What can you conclude about magnetic field strength from this experiment? Repeat the above process again, except this time, decrease the bar magnet's strength to 30% (the slider at the top right). Take 5 readings for 3 distances, and record them in the new table below: Magnetic Field (G) for 30% Bar Magnet Strength Distance 1 Distance 2 Distance 3 Point 1: South Point 2 Point 3 Point 4 Point 5: North 1. What's different compared to the trials above?

Part 3: Earth's Magnetic Field 1. Now select "Show Planet Earth" and "Show Field," turning off the Field Meter but leaving the bar magnet and compass. What do you notice from your earlier diagram about the magnetic field of a magnet and that of the planet Earth? 2. Turn on the Field Meter and drag it around the Earth at different distances. Do for at least four different distances and record the ? readings here: 3. What do you notice about magnetic fields and magnetic field strengths for the Earth?

Reflection Questions: 1. If you are lost in the woods, and you have a compass- would you want to hold it near a magnet as you are trying to find your way? Explain your answer. 2. Does a magnet have to be touching another material to exert a force? Why or why not? 3. The field lines of a magnet move in which direction? 4. As you move away from a magnet, what happens to the magnetic field? 5. If the red on the magnet and compass needle is the North pole, what can we say happens to the needle of the compass as it moves around the magnet?

Page 1 of 5 ZOOM + Lab 5: Magnetic Fields Online Version We will be using the PHeT Magnet and Compass simulation this week. You can find the simulation at: https://phet.colorado.edu/en/simulations/magnet-and-compass/about Introduction: Magnet and Compass To explore how the different options work in this simulation, which is set up a little differently than other simulations we've used so far, start by deselecting all options on the right menu except for the magnet. 1. What do you think the magnetic field produced by the magnet will look like? 2. Check your prediction by selecting the "show field" tab. Were you correct? 3. If you were to chop this magnet in half and separate the pieces, what would be the polarity of each piece? Why? 4. Select the "show inside magnet" tab. Do you still agree with your prediction from above? Why or why not? 5. Deselect the "Show Field" tab. Make a prediction: If you place a compass near the magnet, what will the compass do? Why? 6. Select "Show Compass." Move the compass to several positions around the magnet. What do you notice?Page ofS O zoom + I". Seiect "show planet Earth.\" What do you notice? Are the North and South poies where you expect them to be? Why? 8. Move the compass to various positions around the Earth. Does this confirm your guess about how compasses work? Why or why not? Part 1: Nature of Magnetic Fields Select the tabs \"See Inside Magnet\" and \"Show Compass," make sure \"Show Field\" is turned off, and you shouid have a setup like this: \" "an\" ) of5 O ZODM + El Part 1: Nature of Magnetic Fields Select the tabs "See Inside Magnet\" and \"Show Com pass,\" make sure "Show Field\" is turned off, and you should have a setup like this: i l 1. Drag the compass around to the bar magnet. Watch the red arrow ofthe compass needle. What do you notice about the needle color as you drag it around the magnet? 2. Now click the Flip Polarity button and do the same thing. What do you notice about the needle? 3. Select the \"Show Field\" tab, take a screenshot, and place it here. Alternately, if you've printed out the writeup, sketch what the field looks like around the compass and magnet. 4. Draw a diagrammatic version of this field around the bar magnet below. Place arrows on the field going from North to South. Page 2 of 5 ZOOM 4. Draw a diagrammatic version of this field around the bar magnet below. Place arrows on the field going from North to South. S N Part 2: Magnetic Field Strength Click on the "Field Meter," and focus only on top magnetic field strength value, B.Page