Lesson 11
What is a force?
A push or pull
Scientists and engineers use _____ to give and receive constructive feedback.
peer review
True or false?
Only moving objects exert forces.
False
What is magnitude?
size, how big something is
In every interaction, one object applies a ______ on another object.
force
What force makes an apple fall to the ground?
gravity
What is a field?
A. an area where contact forces cause objects to stop, move, or change direction
B. a type of friction in which air particles collide with the surface of a moving object.
C. an area where energy is stored; a field exerts a noncontact force
D. the measure of how much an object's position changes
C. an area where energy is stored; a field exerts a noncontact force
Which will create more friction?
ice, gravel
gravel
False, they repel
______ is a force that attracts or repels.
(gravity, friction, air resistance, magnetism)
magnetism
What two factors does every force have?
Give two examples of a contact force.
friction, air resistance, elastic force
Which of these is evidence that a field exists?
A. A child pushes a toy car across the floor.
B. A car runs into a pole and bends it.
C. A ball is released and falls to the ground.
D. All of these.
C. A ball is released and falls to the ground.
A _____ is a possible explanation based on observations. It can be tested and measured through experimentation.
hypothesis
When scientists disagree, they always argue from ____.
(opinion, evidence, distant places, preferences)
evidence
1. _________ data is observed with our senses.
2. _________ data involves measurements or numbers.
(quantitative or qualitative)
1. qualitative
2. quantitative
Give two examples of a noncontact force.
magnetism, electricity
Air resistance is a special type of ______?
friction
What causes magnetism?
negatively charged particles that move
How can you increase the strength of a magnetic force on an object?
A. move the object closer to the magnet
B. move the object farther away from the magnet
C. Use a stronger magnet
D. either A or C
D. either A or C
What makes a question scientific?
It can be answered through investigation.
A. Flowers that have no smell are the best for making bouquets.
B. Polar bears have the most interesting behaviors.
C. The north poles of two magnets will repel each other.
D. both A and B
C. The north poles of two magnets will repel each other.
A hypothesis can be tested; the other options use opinions.
Scientists use computers to create a certain type of model. It can gather information about a process or system that is too dangerous, too costly, or even impossible to perform in real life.
This type of model is a ________.
simulation
Name five ways a force can affect an object.
move, stop, speed up, slow down, remain in place, change direction, deform
Hypothesis: A zipper bag keeps lettuce fresh longer than a paper bag does. Identify the variables (independent, dependent, constant)
1. type of storage bag
2. how long lettuce stays fresh
3. type of lettuce used
1. independent
2. dependent
3. constant