Newton force laws
What term describes the combination (sum) of all forces acting on an object?
net force (also called resultant force)
Motion & Acceleration — 100
What is the name for the rate at which velocity changes?
Answer:
acceleration
Gravitational PE — 100
What two quantities affect gravitational potential energy between Earth and an object near its surface?
Answer:
By F=maF=ma, for the same force FF, acceleration a=F/ma=F/m. Larger mass → smaller acceleration; smaller mass → larger acceleration.
Potential Energy — 100
Name two types of potential energy listed in the Ohio standards besides gravitational.
Answer:
elastic potential energy and chemical potential energy
Mixed Review — 100
What is the SI unit of acceleration (symbol plus words)?
Answer:
m/s2 (meters per second squared)m/s2 (meters per second squared)
Newton's Forces — 200
Two forces of 5 N and 8 N act in the same direction on an object. What is the net force (in newtons)?
13 N
Motion & Acceleration — 200
A car increases its speed from 12 m/s to 22 m/s in 5 s. Calculate the average acceleration and include units.
Answer:
Average acceleration =22−12/ 5 = 10/5=2
2 m/s2
Gravitational PE — 200
Explain how gravitational potential energy changes when you lift an object higher above the ground.
Answer:
Gravitational potential energy increases as height increases (more work is done against gravity).
Potential Energy — 200
Give an example of elastic potential energy from everyday life and explain why it stores energy.
Answer:
A stretched rubber band — deformation stores energy that can be released when it returns toward equilibrium.
What time is it?
Time for you to buy a watch.
Newton's Forces — 300
If two equal forces act in opposite directions on the same object, what is the net force called and what is its value?
They are balanced forces; net force 0 N0 N
Motion & Acceleration — 300
Describe how a nonzero net force affects an object’s motion.
Answer:
A nonzero net force produces acceleration, changing the object's speed and/or direction.
Gravitational PE — 300
A 2-kg object is raised vertically by 3 m. Describe qualitatively whether the gravitational potential energy increases or decreases and why.
Answer:
It increases because raising the object increases its height relative to Earth; more energy is stored as gravitational PE.
Potential Energy — 300
Provide an example of chemical potential energy and explain what in the object stores that energy.
Answer:
A battery — chemical bonds and arrangement of atoms store chemical potential energy that can be released in reactions.
What must you do before you move seats?
Ask teacher.
Newton's Forces — 400
State Newton’s third law of motion in one sentence.
Answer:
For every action there is an equal and opposite reaction.
Motion & Acceleration — 400
A roller coaster slows from 20 m/s to 8 m/s in 4 s. Is this acceleration positive or negative? Calculate its magnitude.
Answer:
Acceleration =(8−20)/4=−12/4
=−3 m/s2
This is negative (deceleration); magnitude -3 m/s2
Gravitational PE — 400
Give the relationship (in words) between mass, height, and gravitational potential energy for objects near Earth’s surface.
Answer:
Gravitational PE increases with greater mass and greater height (PE scales with mass and height).
Potential Energy — 400
Explain how compression or stretching changes an elastic object's potential energy (qualitatively).
Answer:
More compression/stretch increases displacement from equilibrium, storing more elastic potential energy (depends on material properties).
How are the students in class to line up?
In a single file, and silently.
Newton's Forces — 500
A 10-kg box is pushed with 30 N to the right while friction exerts 12 N to the left. Calculate the net force and state its direction.
Answer:
Net force =30−12=18 N=30−12=18 N to the right
Motion & Acceleration — 500
Explain why two identical forces acting on different masses produce different accelerations (use Newton’s second law conceptually).
Answer:
By F=maF=ma, for the same force FF, acceleration a=F/ma=F/m. Larger mass → smaller acceleration; smaller mass → larger acceleration.
Gravitational PE — 500
Two identical masses are at different heights. Mass A is at 2 m, Mass B at 5 m. Which has more gravitational potential energy and why? Include how changing mass would affect the comparison.
Answer:
Mass B (5 m) has more gravitational PE because height is greater. If mass increases, PE increases proportionally.
Potential Energy — 500
A compressed spring and a raised rock both store potential energy. Explain one similarity and one difference in how their potential energy depends on the system’s properties.
Answer:
Similarity: Both store energy that can convert to kinetic energy.
Difference: Gravitational PE depends on mass and height; elastic PE depends on the amount of deformation and material stiffness (spring constant).
Back
Answer:
Similarity: Both store energy that can convert to kinetic energy.
Difference: Gravitational PE depends on mass and height; elastic PE depends on the amount of deformation and material stiffness (spring constant).
How does the class room become clearn?
By each studen cleaning up after themselves and helping to clean.