Whether it’s the start of the school year or a fresh semester with a new group of students, it’s important to review science equipment use and safety before diving into experiments.ExploreLearning Gizmosvirtual simulations can help your classes learn, review, and practice with interactive lab equipment to enrich or replace in-person labs.
测量与三光束质量平衡
Atriple beam balancemeasures themass, or the amount of matter, in an object. From apples to paperclips, scientists calculate mass ingrams(g), the basic unit of mass in the metric system.
A triple beam balance works on the principle of the lever. There is afulcrum, the pivot point of a lever, and a set of sliding weights, calledriders, that slide onrider beamsto balance an object. Before calculating the mass of an object, students must “zero” the balance by sliding all riders to the left, ensuring thepointerlines up with thezero mark. Once students set an object on themeasurement tray,the pointer will rise. As the riders move farther to the right (away from the fulcrum), they exert a greater downward force on the beams (and upward force on the measurement tray).
A triple balance beam has three rider beams:
- The front rider beam measures up to 10 grams in 1-gram increments
- The middle rider beam measures up to 500 grams in 100-gram increments
- The back rider beam measures up to 100 grams in 10-gram increments
To calculate the mass, students must slide the riders until the pointer aligns with the zero mark again. The mass of an object is equal to the sum of the masses indicated by the riders. For example, if the pointer lines up with the zero mark and the riders show values of 300 grams, 20 grams, and 8.10 grams, the object’s total mass would be 328.10 grams.
Using Online Labs to Introduce the Triple Beam Balance
Prepare students for triple beam balance work through an online simulation. With theTriple Beam Balance Gizmo, students calculate the mass of various objects as they click, drag, move, and adjust a virtual triple beam balance.
After using the Gizmo, students will be prepared to use a real triple beam balance in the laboratory. This online simulation is also a great substitute for hands-on lab experience if your school cannot access triple beam balances.
Lesson Objectives:
- Identify the parts of a triple beam balance
- Understand that a triple beam balance is an example of a lever
- Find the mass of objects using a triple beam balance
Each Gizmo includes a student exploration sheet, teacher guide, and vocabulary for easy lesson planning and implementation. All documents are fully customizable (Microsoft Word, Google Doc, and PDF versions) to fit your teaching needs. Assessment questions are included in each Gizmo, so you can quickly monitor and assess learning.
Introducing Other Lab Equipment
Looking for other Gizmos to help students learn about lab equipment? Explore these options!
Two-pan balance and spring scale ?Weight and Mass Gizmo
Beakers, graduated cylinders, and pipettes ?Measuring Volume Gizmo
Compound microscopes ?Cell Types Gizmo
Using pH paper ?pH Analysis Gizmo
