Teacher Portal
Simple Machines
Investigation 1
Investigation 1
Simple Machines

Phase 1 – Defined Understanding
Student Guide
Download and Distribute
Access Teacher Guide
Student Guide with answers
Teacher PreLab
Prepare for the Experiment
Phase 2 – Dynamic Understanding
► Investigation One Summary – Lab Goals
In Investigation One, you investigated pulley systems and forces. During this Investigation, you:
1. Measured the force of gravity of each load force.
2. Converted mass in grams to kilograms using the following formula:
3. Calculated load force using the following formula:
4. Using a one-pulley system, measured the force in Newtons (N) to lift a load.
5. Determine the work done on the load and effort distance of the pulley for each load by using the following formula:
Work (J) = effort (N) x distance (load/effort) was applied (m)
6. Calculated the mechanical advantage of each load by using the pulley system by using the following formula:
7. Using a two-pulley system, measured the force in Newtons (N) to life a load.
8. Repeated steps 5 and 6 above using date from the two-pulley system.
► Investigation One Summary – Learning Goals
Through these experiments, you concluded that:
1. Simple machines can change the force needed to lift a load by offering a mechanical advantage. In a one-pulley system, the effort force required to lift the load is identical to the load force. Thus, there is no mechanical advantage in a one-pulley system. However, in a two-pulley system, the effort force is less than the load force. It takes roughly half the amount of force to lift the load. Thus, a two-pulley system has a mechanical advantage of 2. This is offset by the fact that in a two-pulley system, the distance over which the effort is applied is greater than the distance over which the effort is applied in a single-pulley system.
2. Mechanical advantage is the ratio of load force to effort force. If the load force is much greater than the effort force, then there will be a mechanical advantage.
Concept Slides
Launch and Discuss
Mathematics Concepts in This Investigation
- (in)direct relationships
- predict/verify results
- mass in grams
- measuring mass using a triple beam balance
- metric conversion
- decimals to nearest tenth and/or hundredth
- addition
- multiplication
- measuring force in Newtons using spring scale
- calculate work
- manipulating mathematical formulas
- comparing (non)measurable characteristics