Action & Reaction
When you push on a wall, the wall pushes back on you.
👉 What is this an example of?
ACTION AND REACTION FORCES
Forces inside an object are called what?
✅ Answer: INTERNAL FORCES
magnetism, gravity, electrostatic
A hockey puck slows down on ice. What force is acting?
✅ Answer: FRICTION
A rubber band stretching and returning shows what property?
✅ Answer: ELASTICITY
If you jump off a boat, you move forward and the boat moves backward.
👉 Why does this happen?
✅ Answer: THE REACTION FORCE PUSHES THE BOAT BACKWARD
Name 2 types of internal force.
✅ Answer: TENSION / COMPRESSION / SHEAR / TORSION
Name one type of external force.
Answer: APPLIED FORCE / FRICTION / ELASTIC FORCE
A person pushes a shopping cart forward. What force is this?
applied force
Bending a paper clip and it stays bent shows what property?
✅ Answer: PLASTICITY
In an interaction, how many objects are involved in action and reaction forces?
✅ Answer: TWO OBJECTS
What internal force squeezes or squashes an object?
Compression
What force is applied by a person pushing an object?
Answer: APPLIED FORCE
A rope holding a swing is being pulled tight. What force is acting?
✅ Answer: TENSION
What kind of change is elastic: permanent or temporary?
✅ Answer: TEMPORARY CHANGE
What is true about the size and direction of action and reaction forces?
✅ Answer: EQUAL IN SIZE AND OPPOSITE IN DIRECTION
What internal force twists an object?
Torsion
ice skating vs rollerblading outdoors shows a difference in this type of external force
friction
A bridge bends slightly when cars drive over it. What caused this?
✅ Answer: EXTERNAL FORCES CAUSING INTERNAL FORCES
What kind of change is plastic: permanent or temporary?
✅ Answer: PERMANENT CHANGE
A swimmer pushes water backward.
👉 What happens next?
✅ Answer: THE WATER PUSHES THE SWIMMER FORWARD
What internal force pushes parts of an object in opposite directions, causing bending or breaking?
Shear
What type of force causes internal forces inside an object?
external forces
A metal bar twists until it breaks. What two ideas are shown?
✅ Answer: TORSION AND PLASTICITY
A student stretches a metal spring, and it returns to its original shape. Then they keep stretching it until it no longer returns and stays stretched.
What has happened to the material?
✅ Answer:
THE MATERIAL FIRST SHOWED ELASTICITY, BUT AFTER TOO MUCH FORCE IT CHANGED TO PLASTIC DEFORMATION AND STAYED STRETCHED