Tendency of objects to keep doing what they are doing (moving or staying at rest)
100
What is Newton's first law of motion
If a force is acting on an object are balanced, the object will continue doing what it is doing
100
Sharon rides her bike at a speed of 10 m/s. As she rides up a hill her speed decreases to 5 m/s. Is her acceleration negative or positive? Why?
Negative because she is going against gravity
100
Which answer choice on page 117, question 1, is an example of contact force?
B, friction.
200
What is contact force?
A force that must touch an object to change its speed and or direction
200
What is net force?
The amount by which the opposing forces acting on an object are unequal
200
What is Newton's second law of motion?
The acceleration of an object is related to the net force acting on it and the mass of the object
200
Now Sharon rides her bike down the street in 20 seconds. During this time her speed remains constant at 5 m/s. What is the value of her acceleration during this time?
Her acceleration remains constant at 0 m/s.
200
Which answer choice on page 117, question 2, is an example of forces acting on a balanced object?
C, a hot air balloon rising at a constant speed.
300
What is force?
A push or pull that causes something to change motion
300
What is a newton?
A metric unit used to measure force or weight
300
What is Newton's third law of motion?
For every action there is an equal and opposite reaction
300
Dave is driving down the street. If Dave steps on the brakes what force will this cause?
Friction
300
Which answer choice on page 117, question 3, best describes the motion of an object in which the net force acting on it is 0 Newtons?
D, the objects motion is not changing.
400
What is friction?
A force that occurs when two things move past each other and rub together
400
What is noncontact force
A force that acts on an object to change its speed or direction from a distance
400
What is Newton's first law of motion sometimes called?
Law of inertia
400
What causes a ball to speed up as it rolls down a hill?
Gravity
400
Sean pushes a parked car with a force of a 80 Newtons. The car does not begin to move. Which of the following best describes the force the car exerts on Sean.
The same amount of force as Sean
500
What is gravity
A force that acts without physical contact to pull two objects toward each other
500
What is normal force?
The force that pushes up to support the weight of an object
500
What forces slow down a ball while it is in motion after you have hit a home run?
Friction and gravity slow the baseball down while it is in motion
500
Sharon cruises east at 7m/s. She then used her brakes and comes to a gentle stop. As Sharon slows, how does the net force compare to that of her motion.
The net force is west, opposite the direction of her motion (negative acceleration)
500
What force has the greatest influence on the structure of solar systems and galaxies?