Motion Force Teacher Guide - Forces That Affect Motion

Forces That Affect Motion

Time Required



Students will investigate and measure forces by completing a lab.



Pencil3-2-1 Summary from previous lessonLab Sheet: Exploring Forces


Computer and Internet accessA spring (can be a coil spring or a piece from a spring toy)WashersTwo metersticksForce meterTwo or more heavy booksFlat work surface100g hanging mass500g hanging mass


Gather materials for the lab, and make copies of the Lab Sheet: Exploring Forces.
Distribute students’ 3-2-1 Summaries before the Warm Up.

Warm Up: Game Discussion

  • First, have students review and discuss any notes or questions they recorded during game play. Return their 3-2-1 Summaries and have students discuss these as well. Then, call on pairs of students to share their notes, questions, and 3-2-1 Summaries with the class.
  • After students answer the questions below, discuss their responses as a class.
  • What are some different kinds of forces?
    Answers will vary, but students should identify and recognize forces such as gravity, friction, magnetism, etc.
  • What role do forces play in Motion Force?
    Sample Answer: Forces are used to move the spacecraft around obstacles and toward an exit portal. Forces can be used to change the velocity of the spacecraft.


Have students play Motion Force with their partners for approximately 20 minutes. Students should continue where they left off with the previous game by selecting the appropriate mission.

Pause and Think

During game play, ask students to share how the experience is different from the first game play session.

  • Have they learned any new strategies for maneuvering the spacecraft?
  • How many missions have they completed?
  • Have they completed any achievements? If so, how?

Lab: Exploring Forces

Distribute the Lab Sheets and have students review the Introduction and Materials List. As they are reading, distribute the lab materials to each group. Explain to students that they will be working in small groups to complete the lab. Review the procedural steps as a class. Make sure students understand that a force is any push or pull and is measured in Newtons. Remind students that they use Newtons in Motion Force to maneuver their spacecraft.

As students complete the lab, circulate to support as needed, and then review questions A through E from the lab sheet together.

Student Questions:

  • What is the relationship between the amount of stretch and the number of washers?
    The amount of stretch increased proportionally as the number of washers was increased.
  • In the experiment, the washers exerted a force on the spring. Now you are going to use a force meter to measure forces. Hang the 100g mass on the force meter. How much force is required to hold the mass?
    1 N
  • Repeat step H with the 500g mass. How much force is required to hold the mass?
    5 N
  • Use the force meter and the washers to find how many washers exert 1 N of force.
    Answers will vary depending on the size of the washers. Typical washers are 25 g, so it should take about 4 washers to exert 1 N of force.
  • Now that you are familiar with 1 Newton of force, estimate the force needed to lift the following objects. Remember, it took 1 N to hold the 100g mass. You can hold the 100g mass in your hand to get an idea of what lifting 100 grams feels like.
    • basketball (approximation: 6 N)
    • science textbook (approximation: 9 N)
    • stapler (approximation: 2.5 N)
    • hammer (approximation: 5 N)

Exit Slip

Have students complete the Exit Slip activity in the Student Guide and submit the activity before leaving the classroom. Review the student responses before the next lesson.