Forces A
What is elasticity?
When an object returns to it's shape after a force acts upon it.
What is plasticity?
When a material permanently changes shape after a forces acts on it.
What is tension?
Pulling
What are the three types of matter?
Gas, solid, liquid
What are the 6 steps of the scientific method?
Question, Hypothesis, Materials, Procedure, Observations, Conclusion
What is compression?
Pushing together.
What is shear?
Cutting force.
What is torsion?
Twisting
What happens to particles when heated?
Speed up and expand.
Why do we use the scientific method?
Various answers.
List two examples of a non-contact force.
Magnetism, electric or gravity.
What is the difference between an internal force and an external force?
Internal is happening inside the object (tension, shear, compression, etc.) and external is what is causing it to do that (wind, someone's hand, sitting on a chair).
Does a solid object (like a chair or desk) still experience compression even if it doesn't move with pressure? Explain.
Yes - the particles are still being compressed.
What happens to particles when cooled down?
Slow down and contract.
What should a scientist do while/after observing an experiment?
Record the results.
Give an example of a reaction force.
The ground pushing back when you jump
The recoil you feel when shooting a basketball
The bounce back when you press down on a trampoline
List three types of friction
Static, rolling, sliding.
Explain how a bridge experiences two forces at the same time (and what are the forces?).
Compression on the bottom and tension on the top.
Particles expand when heated and since it can't go out it goes up.
What is wrong with the following experiment:
A scientist wanted to know how fertilizer affects plant growth. He gave a tomato seed 1 liter of water each week with fertilizer and gave an apple seed 2 liters of water each week without fertilizer.
Too many manipulated variables.
What is the difference between an action force and a reaction force?
An action force is a force that is applied to an object, which then acts in a particular direction.
A reaction force is the force that acts in the opposite direction of an action force.
Explain why when a bouncy ball is dropped, every time it will bounce lower and lower until it stops.
Gravity (a non-contact force) is acting on it along with air resistance.
What is Newton's third law of motion?
Every action has an equal and opposite reaction.
Explain how cracks in sidewalks happen.
Weather causes particles to expand and contract, causing small cracks. The cracks get filled with rain water and when frozen will expand, causing the crack to become bigger.
What are the three types of variables in a science experiment?
Controlled, manipulated, responding