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1. When one says physics is the most fundamental science, what does that mean with regards to all other sciences?
Explain why biology would be considered the most complex science, even though some would argue since it does not involve mathematics, it can't be.
2. What were the two problems with how Aristotle tried to explain the physical world? 1.
2.
For almost 2,000 years, people believed his ideas without question. What happens when we don't question certain truths and accept them based solely on the fact they were said by a person of authority?
Explain how you have done the same thing: accepted truths without question. Give one specific example from your life.
As you embark on true scientific discovery in this class, in what ways will you have to change your way of thinking with regards to questioning, critically thinking, and problem solving?
3. What did Galileo do to change the way people look at science?
Why did it take so long for someone to challenge Aristotle's notions: what was going on in history during this time?
If someone had challenged Aristotle's ideas earlier in history, do you think we would be farther along in our knowledge of science, or would we be at about the same place? Make an argument for your opinion.
The term science was defined in class. Explain that term in your own words.
4. Determine whether or not the following statements qualify for a hypothesis. Answer yes or no and explain why.
5. Outline and describe the five steps to the scientific method. One:
Two:
Three:
Four:
Five:
What is often misunderstood when people say, “oh, that is just a theory”
In our alien example in class, if our technology improved to allow us to look inside the cars, would we have to modify or completely throw out our theory? Explain.
Cite an example where that has happened based on your learning from other science courses.
6. What is the major key to why we use significant digits?
If a certain measuring tool of time was accurate to the millisecond (milli is one thousandth of a second: ie. .001 is 1 millisecond), but your measuring tool for distance was only accurate to the centimeter (ie. .20 is 20 cm), would this answer be correct: (.20 cm)/(1.543 s) = .129617 cm/s?
If it is not correct, explain what is wrong:
Give the answer with the correct significant digits:
Given this number, 1.0242, how many digits are significant?
Which number is the least certain?
Explain why citing an example to defend your answer:
7. In the direct straight line relationship, how does y change as x changes?
If x were to increase by a factor of 5, how would y change?
In the car example, if you wanted to slow down to 1/4 your current speed, what would you have to do with the gas pedal?
8. In the inverse relatinship, how does y change as x changes?
If x were to decrease by a factor of 4, how would y change?
How is this relationship similar to the direct straight line relationship?
How is it different?
9. In the direct square relationship, how does y change as x changes?
If x were to increase by a factor of five, how would y change?
If you wanted to slow down to 1/9 your current speed, what would you have to do to the gas pedal?
If your car's gas pedal worked like this, why would you need to be careful when taking off from a stoplight?
10. In the inverse square relationship, how does y change as x changes?
If x were to decrease by a factor of six, how would y change?
How is this relationship similar to the inverse relationship
How is it different?
11. In the direct square root relationship, how does y change as x changes?
If x were to increase by a factor of 25, how would y change?
Explain what would happen to your speed if you pressed on the gas pedal nine times as much if it operated under this relationship.
Would this be a good car to have? Why or why not?
12. A car travels 4.0 miles across town in 20.0 minutes. Find the average speed in miles per hour. (12 mph)
The same car makes the same trip with an average speed of 20.0 mph. How long will it take the car to travel the 4.0 miles? (.20 hours or 12 minutes)
The same car makes a different trip with an average speed of 25 mph for 30.0 minutes. How far will it travel? (12.5 miles = 13 miles with correct sig digs)
What happens to speed if distance stays the same but the time gets smaller?
What happens to speed if distance stays the same but the time gets larger?
What relationship does speed have with time?
If you double the amount of time it takes to make a trip, how much does your speed change?
13. A pitcher throws a baseball at 90.0 mph. How much time does it take the ball to reach the batter 60.0 feet away? (.455 s)
What does that tell you about a batter's ability to determine where the ball is going?
FIRST HOUR: Stop here. Don't do 14 for tonight's homework! 14. Sketch two distance vs. time graphs that show an object traveling a certain speed in one, and twice as fast in the other. (This is just a sketch so you don't need numbers, but label the axis)
Sketch a graph that shows an object starting out fast but it slows down. (The one in class shows an object starting out slow, but speeds up).
A car travels at 100 km/h for 2.0 hours, at 60 km/h for the next 2.0 hours and finally at 80 km/h for 1.0 hours. Find its average speed for the entire trip. (80 km/h)
15. A car heads north for 100.0 meters, and then heads west for another 50.0 meters. Find the displacement of the car. (112 m NW)
If the car did it in 10 minutes, find the average velocity in m/s. (.186 m/s NW).
Find the average speed of the car in m/s. (.250 m/s)
Why is velocity more useful than speed?
If a car heads south 300.0 meters, in which direction and how many meters does the car need to travel in order to have an average velocity of 50.0 m/s SE if the trip took 10.0 seconds?
If the car headed south again at 300.0 meters, in which direction and how many meters does the car need to travel so that the average velocity and average speed would both be 30 m/s if the total trip took 20 seconds?
16. Distinguish the similarities and differences between distance and displacement.
Distinguish the similarities and differences between speed and velocity.
If a car headed north 100.0 meters in 10.0 seconds, what would its average speed and average velocity equal? (avg speed = 10.0 m/s; avg velocity = 10.0 m/s N).
Why are they equal?
If a car travels 10.0 Km North, turns left and travels 10.0 Km West, then turns left again and travels another 10.0 Km South, and finally turns left one more time and travels 10.0 Km East, find its average speed if the trip took 6.0 minutes in m/s (Draw the picture of this too). (111 m/s).
From the last problem, what would be the car's average velocity for the entire trip? Explain why.
17. What information can you gather from a displacement vs. time graph?
List the similarities and differences between a distance vs. time graph, and a displacement vs. time graph: (You should have at least three similarities and three differences).
Sketch a graph of the following situation: a person starts from a zero position and walks a certain speed for a certain amount of time, then stops for the same amount of time, then walks back to the starting position with half the original speed. Even though this is a sketch, make sure your slopes reflect the differences, and your time intervals (the length on the x-axis) are correct).
Sketch a graph of the following situation: a person starts + 10.0 meters from the starting position and walks towards the starting position with a certain speed, and stops to rest after 5.0 meters for the same amount of time he spent walking. Then, the person decides to walk back to the + 10.0 m position with twice the original speed.
Consider the following graph: 
Could this graph represent a distance vs. time graph? Why or why not?
Sketch a graph of the following situation: A person starts out +5 m from the zero position at rest for a certain amount of time. Then, the person walks in the positive direction for the same amount of time a certain speed. Then, the person walks in the negative direction to the zero position in half the time of the last interval.
Sketch a graph of the following situation: A person starts - 10 meters from the zero position and walks towards the zero position with a certain speed for a certain amount of time. When the person reaches the zero position, she rests for the same amount of time as the previous time interval. Then, the person continues in the positive direction with twice the speed and half the time as the previous time interval, and then rests.
Sketch a graph of the following situation: A person starts - 10 meters from the zero position not moving for a certain amount of time. The, he walks towards the zero position with a certain speed for the same amount of time, and during that time passes the zero position and ends up 10 meters to the right of the zero position. Then, the person rests for the same time amount of time, and then walks back to the zero position with twice the time as the original time intervals.
Sketch a graph of the following situation: A person starts at the zero position with a certain speed, and immediately slows down to rest in a certain amount of time. Then, the person rests for the same amount of time. Then, the person speeds up in the negative direction, and as soon as she passes the zero position, slows down to a stop (that entire time interval is twice the time as the original time).
18. Explain why the units for acceleration is m/s^2 (read either meters per second squared, or meters per second every second).
A car starts from rest and reaches a velocity of + 30 mph in 3.2 seconds. Find its acceleration in m/s^2. (+ 4.2 m/s^2)
After reaching that speed, it maintained + 30 mph for 5.0 seconds, and then began slowing down to rest in 4.5 seconds. Find its acceleration in m/s^2. (- 3.0 m/s^2)
Sketch a graph of the car's motion from the previous two levels. In your sketch, label the x and y axis, and since you are given time and speeds, use tick marks on the x and y axis.
If a car started from a speed of 10.0 m/s and accelerated to 25 m/s with an acceleration of 5.0 m/s^2, how long did it take to do so? (3.0 s)
19. A baseball traveling at 90 mph is struck by a bat and flies off in the opposite direction with a speed of 70 mph. If the impact time was .0021 seconds, find its acceleration in m/s^2. (-34,000 m/s^2).
How is it possible to have such a huge acceleration, and why isn't the ball traveling any faster after the hit? (The two reasons discussed in class).
A tennis ball starts out traveling 25 m/s and is struck by a racket which causes it to fly off in the opposite direction. If the impact time lasted .0110 s and it's acceleration was - 5,000 m/s^2, what is the ball's final velocity? (- 30 m/s).
Consider the graph below and answer the following questions: 
In which time interval(s) is the acceleration negative?
In which time interval(s) is there no acceleration?
Which time interval has the greatest acceleration?
Which time interval has the smallest acceleration?
In which time interval(s) is the object speeding up?
In which time interval(s) is the object slowing down?
Sketch a graph for the following situation: a car starts out traveling + 20 m/s for five seconds, and then slows down to + 10 m/s in 3 seconds. It maintains that speed for another two seconds, and then slows down to a stop in 2 seconds.
Draw what that same situation would look like for a speed vs. time graph.
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