Newton's Laws
What is the term that describes an object's tendency to resist change in velocity (as described by Newton's First Law)?
Inertia
If you dropped a rock and a feather in a vacuum on earth, which would hit the ground first?
They would hit at the same time.
Which force allows a car to accelerate when the light turns green?
Friction
A student pushes a 15 kg sled across the ice, causing it to accelerate at a rate of 4 m/s2. What is the net force acting on the sled?
60 N
What are the two valid units for acceleration?
m/s2 and N/(kg)
If you increase the force acting upon an object, does the acceleration increase or decrease?
Increase
Which two factors determine the strength of gravity between two large objects?
Mass and distance between the objects
Which two factors determine the strength of friction force?
Normal force (weight) and coefficient of friction (roughness)
If you have a mass of 70 kg and the acceleration on Earth is 10 m/s^2, what is your weight?
700 N
What must happen for an object's velocity to change?
If you increase the mass of an object without changing the amount of force acting upon it, will the acceleration of that object increase or decrease?
Decrease.
If you dropped a rock on the moon and a rock on Earth at the same time, which would hit the ground first?
The rock on Earth, since the gravity is stronger there.
Which of the following would have the LEAST amount of friction?
A. A low mass car with a low coefficient of friction (𝜇)
B. A high mass car with a low coefficient of friction (𝜇)
C. A low mass car with a high coefficient of friction (𝜇)
D. A high mass car with a high coefficient of friction (𝜇)
A
A 50 kg box is pushed at a constant acceleration of 20 m/s^2. What is the force acting upon it?
1000 N
What forces are acting upon an object that is in free fall?
Gravity only
What is the one factor that determines how much inertia an object has?
Mass
When an object is in free fall, does the acceleration increase, decrease, or stay the same as the object gets closer to the ground?
Stays the same.
How would you write the friction equation to solve for coefficient of friction?
μ= f/(Fn)
What is the force of gravity between two planets that have masses of 50 units and 40 units and that are 5 units apart?
80G
How would you write Newton's Second Law to solve for acceleration?
a= F/m