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Home Concept Builders Newton's Laws Normal Force Card Sort Directions

Normal Force Card Sort - Directions

Using the Normal Force Card Sort Concept Builder is quite simple. You will be presented with a card depicting a physical situation involving an object and a scale. The scale measures the normal force acting upon the object that is touching the top plate of the scale. You have to sort the card into one of four categories:

  1. Category A: The Normal Force is equal to the Object's Weight
  2. Category B: The Normal Force is greater than (>) the Object's Weight
  3. Category C: The Normal Force is less than (<) the Object's Weight
  4. Category D: There is not enough given information to place the card into one category


Every card is numbered. (The numbers are random so Card #1 for you might not match Card #1 for a classmate.) You can sort a card into a cateogory by tapping on any one of the category boxes. When you tap on the box, the card's number is placed inside the box. If you tap on the same box a second time, then the card is removed from that category. If you tap on a second box, the card is sorted into the newly tapped category. Once you have sorted a card, tap on the Previous or Next Arrows to view the next card. Once all your cards have been sorted, a Check Answers button appears. If you are satisfied with your category sortings, then you can tap on the Check Answers button. If at any time you wish to Unsort all cards and start over with a blank set of sorts, then tap on the Unsort button.

When you tap on the Check Answers button, your answers will be evaluated and a Progress Report will be given. You will be told the number of correct categories an given an opportunity to try again. However you are not told which card sorts are incorrect (sorry about that). But that's no problem because you can try as many times as you like and your progress will always be updated. Don't go randomly guessing though just because you have an infinite number of attempts. Use your Physics understanding! And if you're not comfortable with that, then use the Help Me! button. Tapping on Help Me! opens up a page in a different browser tab that explains the details of how to think about the situation. If you start randomly guessing, then your teacher is going to know it because the Concept Builder keeps track of everything (even the number of times it hears you swearing ... should you succumb to that). And a Health Rating is calculated after each tap on the Check Answers button. (If you are interested, then you can learn more about the Health Rating here.) Once you have finally perfected the card sorts, you will earn the infamous trophy for that difficulty level and it will be displayed on the Main Menu screen. Of course if you're not happy with your Health Rating (and think your friends will laugh at you), then you can try the Difficulty Level again and improve it. Your highest Health Rating will always be displayed on the Main Menu screen.

Concept Builder Teacher Notes