Make your own sand clock (timer), in the presence of an adult.
Step 1: Join the tops of two bottle caps using strong glue.
Step 2: Make a small hole with a fine needle at the centre of the joined caps.
Step 3: Fill one bottle halfway with fine sand and close with the joined caps.
Step 4: Attach the second bottle on the other side of the joined caps.
Step 5: Time how long it takes for sand to shift from one bottle to the other using a clock.
How it works: The sand clock measures time by how long it takes for sand to flow from one bottle to the other. The time measured depends on the size of the hole and amount of sand.
Explanation
The chapter provides detailed instructions for making a sand clock using two transparent bottles, caps, strong glue, and fine sand. Students learn that sand clocks were historically used to measure time duration. The time measured depends on the size of the hole and amount of sand.
Solution Steps
Step 1: Join the tops of two bottle caps using strong glue.
Step 2: Make a small hole with a fine needle at the centre of the joined caps.
Step 3: Fill one bottle halfway with fine sand and close with the joined caps.
Step 4: Attach the second bottle on the other side of the joined caps.
Step 5: Time how long it takes for sand to shift from one bottle to the other using a clock.