Mass vs. Weight
Product Number: EB-2010-09-00026-SSC
What is Mass vs. Weight?
We often confuse the terms "mass" and "weight" and use them interchangeably even though they have very different meanings.
We can measure weight here on Earth, but not in the microgravity environment on the International Space Station (ISS).
Mass plays a critical role in the activities and experiments performed by the astronauts. Mass does not change whether it is measured on Earth or the ISS. Weight can change depending upon the gravitational pull such as on the Moon where weight is reduced to one-sixth that of on Earth.
Each activity in the Mass vs. Weight series demonstrates the difference between mass and weight by comparing results with video clips filmed by astronauts performing similar activities onboard the ISS. Students perform the activities in the classroom, record, analyze, and interpret their data. Following data analysis, they observe video of astronauts performing similar demonstrations on the ISS. The activities focus on Newton's Second Law of Motion.
Force = mass x acceleration
This series of activities is based on video education demonstrations presented by crew members Robert Thirsk, Koichi Wakata, and Nicole Stott during the 2009 Expedition 20 mission on the International Space Station.
- To demonstrate the difference between mass and weight by integrating classroom activities with video filmed by astronauts in the microgravity environment on the International Space Station (ISS)
- To explore careers in space exploration
- To explore the international partnerships involved in the International Space Station development, construction and operations
Activities and Videos
Careers in Space
Students will be introduced to the three ISS astronauts who are featured in the Mass vs. Weight video clips. Students will learn about their backgrounds, experiences, interests, and careers. This information will guide them to understand the importance of these factors in why the astronauts chose their career. Students will discuss their own backgrounds, experiences and interests and explore space exploration careers that interest them.
Students measure the amount of force gravity exerts on objects of different mass by suspending them on rubber bands then measuring the distance the rubber bands stretch. Students will collect and discuss their data and compare it to video results of a similar experiment done on the International Space Station.
Air Powered Mass
Student teams build a mass car and measure the movement of the car with varying amounts of mass as a given force is applied. A blast of air from an air pump will accelerate the car across rollers. During a set of experiments, students will vary the mass being carried by the mass car and measure how far the car rolls each time in response to the air blast. Once the experiments are completed, students will graph, discuss their data and compare to video results of a similar experiment performed on the ISS.
Students explore Newton’s Second Law of Motion by attaching an empty (air-inflated) foil drink pouch to a spring release tape measure, and measure the time it takes the pouch to travel one meter as the tape is automatically retracted. The same process will be repeated using a full (fluid-filled) pouch. Which drink pouch will accelerate the fastest -- the full one with the greater mass or the empty one with the lesser mass? Once this experiment is completed, students will discuss their data and compare it to the video results of a similar experiment done on the International Space Station
Design Your Own Experiment
Students design their own International Space Station experiment. They outline their objective and what they hope to accomplish with it. They explain their experiment design, how it works, and what materials they will need for it to be successful. They will also develop questions they would want other students to answer after those students would observe the experiment if it was performed in the microgravity environment of space.
Mass vs. Weight Poster and International Partners Classroom Activity