What is Newton's 2nd Law (using math)?
acceleration = ΣForce / mass
When we graph motion, what physical quantity goes on the horizontal axis?
Time
What is the equation for velocity?
velocity = (xf - xi) / (tf - ti)
What is the first part of Newton's 1st Law?
An object at rest will stay at rest unless acted on by an outside net force.
What are the two ways we can find acceleration?
acceleration = change in velocity / change in time
acceleration = Force / mass
If a ball of 3 kg and a ball of 5 kg are accelerating at the same rate, which one do we have to apply more force to?
The 5 kg ball
For a Position vs Time graph, if an object is not moving what will the graph look like?
What is velocity?
Speed in a direction
What must the Fnet be for an object to remain at rest?
Fnet = 0 N
If you are accelerating, what is happening to your velocity?
Your speed or direction are changing.
Is force directly proportional or inversely proportional to acceleration?
Directly Proportional
For a position versus time graph, what does the slope of the line represent?
Velocity
20 miles / 30 minutes = 0.67 miles / minute North
OR
20 miles / 0.5 hours = 40 miles / hour North
What is the second part of Newton's 1st Law?
An object in constant motion will remain in constant motion unless acted on by an outside net force.
You throw a 2 kg ball with 10 N of force. What is the acceleration of the ball?
10 N / 2 kg = 5 m/s / s OR 5 m/s2
Is mass directly proportional or inversely proportional to acceleration?
Inversely Proportional
Name 3 things you must always include on a graph.
Title, axis labels/units, evenly spaced scale, or data
How do you represent velocity in a motion diagram?
What word describes the motion of an object where the net force is zero?
Inertia
If you are moving in the positive direction and speeding up, is your acceleration positive or negative?
Acceleration is positive.
A model rocket with a mass of 0.05 kg pushes up with a force of 5 N. If earth is pulling down with 0.4 N, what is the rocket's acceleration?
ΣF = 5 N - 0.4 N = 4.6 N
a = 4.6 N / 0.05 kg = 92 N
For a Position vs Time graph with 2 sets of data plotted on it, what does it mean if the lines intersect?
It means they were in the same place at the same time. They crashed!
A bowling ball is rolled down a lane which is 60 feet long. If it takes 2.4 seconds to roll the length of the lane, what is it's velocity? (Assume that towards the pins is negative)
60 feet / 2.4 seconds = - 25 feet / second (towards the pins)
Draw a force diagram of a grocery cart being pushed, but traveling at a constant speed.
A train arrives at a station. It was traveling at 80 m/s and took 40 seconds to stop. What was it's acceleration?
0 m/s -80 m/s / 40 seconds -0 seconds = - 2 m/s /s
OR - 2 m/s2