7th Grade 08/22/2019

LEARNING OBJECTIVES

• Define mass as the amount of matter in an object. 
• Define weight as the force of gravity on an object. 
• Use a balance to measure mass. 
• Use a spring scale to measure weight. 
• Discover that the weight of an object changes when it is moved to another planet. 
• Discover that the mass of an object is constant regardless of where it is located. 

VOCABULARY

• balance, force, gravity, mass, newton, spring scale, weight

ASSIGNMENT

Part 1 : Prior Knowledge Questions (Do these BEFORE using the Gizmo.)

1. Your weight is the pull of gravity on your body. Suppose you step on a bathroom scale onthe Moon. How would your weight on the Moon compare to your weight on Earth?
   A. greater on the Moon B. less on the Moon C. same on Earth and the Moon
2. Your mass is the amount of matter, or “stuff,” in your body. How would your mass on theMoon compare to your mass on Earth? A. greater on the Moon B. less on the Moon C. same on Earth and the Moon

Part 2 : Definition

• Search on internet the definition of mass and write it down in your notebook
• Search on internet the definition of weight and write it down in your notebook

Part 3 : Gizmo Warm-up

On the Weight and Mass Gizmo, you can use a balance to compare the masses of objects.

1. Place the dog on the right pan of the balance. What happens? _____________________________
2. Place the 5-kilogram (kg) mass on the other pan. Which has more mass, the dog or the 5-kg mass?__________________________________________
3. The 5-kg mass is heavier than the dog, so take it off the pan and place a 1-kg mass on the pan. Add 1-kg masses to the left pan until it goes down. Then take one of the 1-kg masses off the pan so that the masses are above the dog.
4. Use this process of adding and subtracting other masses from the left pan until the two pans are balanced. Add up all the masses on the left pan. This is equal to the mass of the dog.What is the mass of the dog? _________________________________________________ You can check your answer by clicking the center of the cross beam of the balance.