Examine a pair of gears that drives a conveyor belt to an oven, including cases where the belt gear is larger than the driver gear. Notice that the number of rotations for each gear depends on the gear size (number of teeth). Explore the relationship between the number of teeth and the number of rotations. Build a table to compare rotations for a range of gear sizes. Look for a pattern in the number of rotations. Choose a gear to adjust the speed of the conveyor belt. For example, choose a gear size (40 teeth) that will turn 1.5 times for every turn of the driver gear (60 teeth). This learning object is the fourth in a series of six objects that progressively increase in difficulty.
Objective
1. Students use knowledge of factors and multiples to solve problems.
2. Students apply ratios to solve multiplicative problems.