Download Integrated Physical Science: Semester 2 Exam Review

Integrated Physical Science: Semester Two: Unit Three Exam Review
Scientific Method
1. What are the steps in the scientific method?
2. What is the difference between independent and dependent variables?
Speed and Motion and Newton’s 1st Law
3. What is the formula for speed? What are the units for distance, time, and speed?
Units:
distance-meters (m)
time- seconds (s)
speed- (m/s)
4. What is Newton’s 1st law?
An object at rest stays at rest and an object in motion stays in motion until either are acted on by a force
5. What is the x-axis, y-axis, on a distance vs time graph and what does the slope tell you?
Y- distance
X- time
Slope tells you speed
6. Draw a motion graph for someone going at a constant speed:
7. If a person travels to Lansing, 100 miles away, and travels for 2 hours, how fast does he travel?
s=d/t
s = 50 mph
8. What distance away is Hart Middle School if you walk for 10 minutes at a speed of 2 m/min?
d = st
20 m
9. What is a vector quantity and what are the 3? What is not a vector quantity?
A vector quantity is something that needs to have direction included
Force, Acceleration, and Velocity are vector quantities
Speed is not a vector
10. The graph below represents the motion of a moving vehicle. What is the average speed of the
vehicle during the time interval from t = 0 seconds to t = 4.0 seconds?
s = 7.5 m/s
11. What is inertia?
An objects resistance to change its current state of motion
12. Why does a semi truck have more inertia than a Volkswagen beetle?
Semi truck has more mass
Acceleration and Newton’s 2nd Law
13. What is the formula for acceleration? What are the units for acceleration?
Units are m/s2 which is the same thing as m/s/s
14. On a speed vs. time graph, what are the labels for the x and y axis and what does the slope give you?
X- time
Y-speed
Slope is acceleration
15. If a car comes to a stop in 3 seconds from 60 miles per hour, what is the car’s acceleration?
-20 mi/hr/s
16. If a car goes from 0-60 mph in 2.5 seconds, what is the car’s acceleration?
24 mi/hr/s
17. Draw a force diagram for the following include applied force, normal force, frictional force, and
gravitational force:
a. A book sitting on a table
b. A box sitting on a table being pushed with a force of 10 N against a frictional force of 2 N
18. What is meant by the term equilibrium and what can an object in equilibrium be doing (2 things)?
Equilibrium is when the net force on an object is equal to zero. An object in equilibrium will either be at
rest or moving at a constant velocity.
19. If an object has a net force other than zero, what is happening to the object?
Accelerating, decelerating, changing direction
20. Is a car moving around a circular track accelerating? Why or why not?
Yes, to change its state of motion a force has to be applied. A force has to be applied to make an object
change direction.
21. What is the formula and units for force?
f = ma f=force
Units are Newtons (N)
m = mass
a = acceleration
22. What is Newton’s second law?
f =ma, If an object is to change its current state of motion (motionless or moving at a constant speed) a
force must be applied. The force applied will cause the object to accelerate, decelerate and or change
direction.
23. What are some units of mass, force, and acceleration?
Mass- kilograms (kg)
Force- Newtons (N)
Acceleration- meters per seconds squared m/s2
24. What is the difference between mass and weight? Explain what the term losing “weight” really means.
Mass is how much matter you are made up of. Weight is how much force gravity is accelerating your mass.
Depending on the gravitational force of an object it will have a certain gravitational acceleration. The
stronger the gravitational force the faster the acceleration. The faster the acceleration the more it will pull
down on your mass so that means you are pushing down on the ground with more force. Gravitational
force will not alter your mass but it will alter your weight.
Losing weight really means your mass is being accelerated by gravity at a slower rate.
25. If a 2 kg mass is pushed with a force of 8 N to the right against a 4N force of friction, what is the
acceleration of the mass?
2
2 m/s
26. If a car has an acceleration of 30 m/sec/sec and has a mass of 200 kg, what is the force acting on the
car?
6000 N
27. What is negative acceleration?
Deceleration
28. What happens when a force is unbalanced?
An object will accelerate, decelerate and or change direction
Newton’s 3rd Law
29. What is Newton’s 3rd law?
Every action has an equal and opposite reaction
30. Explain how an interaction works when you push on a wall with a force of 5 N.
The wall pushes back on you with 5 N.
31. If the force of a bat against the ball is the action force, what is the reaction and why?
Ball against bat
32. If I push on a skateboard with 8N and am going at a constant speed what is the frictional force being
applied?
8N
33. What force opposes motion?
FRICTION!!!!
34. If an objects net force equals zero it is in what? What will it do? If it changes directions will the net
force remain zero?
Equilibrium, remain motionless or move at a constant speed NO!
Gravity and Circular Motion
35. What is G? Why is it different than g?
G represents the 6.674 x 10 -11 value that we give gravity everywhere in the universe and need it when
finding the gravitational force between two objects. We call this the universal gravitational constant. Little
g is the acceleration caused by an objects gravity.
36. What causes the tides on Earth?
Moon’s gravity pulling on Earth
37. What is the weight of a 50 kg object on Earth?
490 N
38. When gravity is the only force acting on an object what do we call it?
Free fall
39. If a baseball is dropped how far has it fallen after 5 seconds and how fast is the ball traveling?
d= 1/2at2
d= 122.5 m
v=at
v= 49 m/s
40. What is terminal velocity and how does it relate to surface area?
Terminal velocity is when the force of gravity’s acceleration is equal to the friction of air resistance. The
more surface area the more air resistance.
41. Will a ball on a string moving with a uniform circular motion experience a change in velocity? What
path will it follow if the string is cut?
Yes a change in direction is a change in velocity. The ball will fly off in a straight line.
42. What is it called when the force of gravitational acceleration is equal to air resistance? Draw a picture
of this.
Terminal velocity
43. Imagine two objects in space that are gravitationally attracted to each other. What would happen to
the gravitational force if:
a. Their distances doubled
b. Their masses doubled
c. One mass was doubled
d. Both masses are doubled and the distance is doubled
44. If a man with a weight of 800N was on top of a ladder that was as tall as the Earth’s radius what would
his weight be?
800 N / 4 = 200 N
45. Why don’t we feel each others gravitational force?
The force is so small we cant feel it.
46. How are mass and distance related to gravitational force?
The more massive an object the stronger the gravitational force. If an object doubles in mass it will
have twice the gravitational force. If an objects mass is cut in half it will have half of the gravitational force.
Distance is a bit different because it involves the inverse square law. If the distance is doubled
between two objects the gravitational force between them becomes ¼ of what it was before their distances
were doubled. If the distance between two objects is cut in half the gravitational force between them
quadruples.