Download 1st Semester Review

First Semester Review for Physics
Learning goals are written in italics, practice exercises are numbered. You will find the equations on the last page.
Show work for all calculations by writing Given, Find, Equation in term of the unknown, substitution of values with
units and Check. You should answer questions on separate sheets of paper. Keep this organized.
Section 2.2 Constant Speed and Acceleration
Define vector and scalar and use definitions to differentiate between them.
1. What is the difference between distance and displacement.
Explain difference between average and instantaneous velocities and speeds
2. Provide a scenario in which the average speed of a runner is greater than its instantaneous speed.
Define in words, and equation: average and instantaneous, velocity and speed. Differentiate between them.
3. Explain the difference between velocity and speed
4. Explain why is it possible for a truck that collects milk from farms to have an average velocity of 20.0
miles/hour if when its minimum speed while in motion was 30.0 miles/hour
Solve problems around average velocity using the correct equation by writing Given, Find, Equation in term of the
unknown, substitution of values with units and Check.
5. Find the average velocity of a race car that starts 15 m behind the starting point and is 100.0 m in front of
the starting point 3 seconds later.
6. Calculate the time it takes a police cruiser to cover 50.0 km at an average speed of 80.0 km/h.
Define average acceleration in words and equation
7. Explain what happens to the velocity of an object that starts from rest and accelerates at -10.0m/s2
Solve problems around average acceleration using the correct equation by writing Given, Find, Equation in term of
the unknown, substitution of values with units and Check.
8. What is the final velocity after 3.0 seconds of an object that accelerates at -9.8 m/s2?
9. A motionless space craft begins to fall towards an exoplanet (a planet outside of our planetary system).
Calculate the average acceleration if given that it reaches 50 m/s in just 3.0 s
10. What is the acceleration of an object whose velocity goes from 55 m/s to 30 m/s in 5.0 s?
11. What would be the final velocity for a swimmer that accelerates at 3 m/s2 from an initial velocity of -10
m/s after 4.0 s?
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Section 1.2 Measurement
Describe uncertainties in measurements
12. Explain what is meant by “uncertainty in measurements”?
Describe and explain the differences in accuracy and precision.
13. Produce a set of measurements that are
a. Accurate, but not precise. Make sure to explain why you did what you did.
b. Precise, but not accurate. Make sure to explain why you did what you did.
Describe the difference between random and systematic errors in measurements
14. Give an example of systematic error in a set of measurements, and an example of random error in a set of
measurements.
Explain the need for significant figures by describing precision and uncertainty
15. Use the words precision and uncertainty to explain why 235s x 1 = 200s
16. Determine the number of significant figures for:
a. 0 m/s
b. .004 g
e. 34.00 m
c. 1001 kg
f. 86700.00 N
d. 1000 s
g. 9000. s
Apply significant figures to all calculations
17. Find the answer with the correct number of significant figures. Calculator answer given.
l. 3.14259 mm * 1 mm =3.14259 mm2 =?
h. 456 m * 0.001 m = 0.456 m2 = ?
i. 500 N /25. Kg =12,500 m/s2=?
m. 23.456 g + 987.6 g = 1011.056 g = ?
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j. 33.56 kg x -9.81 m/s = -329.2236 N =?
n. 7.0 m – 6.677 m = 0.323 m = ?
k.
.
.
= 420 m/s = ?
Distinguish between quantitative and qualitative observations
18. Two students are watching a kicker practicing kicking field goals. One student is making quantitative
observations of the force, and acceleration, initial velocity and final velocity of the kicked footballs,
while the second student is making qualitative observations of the force, acceleration, initial and final
velocities of the kicked footbals. Write down what a set of quantitative observations the first student
might write down, and the matching set of qualitative observations the second student might write
down.
Section 2.1 Newton’s First law
Explain what inertia is and how we measure it.
19. Explain why increasing the speed of an object does not increase the inertia of an object.
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Describe Newton’s 1st Law of motion.
20. Using Newton’s 1st Law, explain why a soccer ball when kicked will eventually come to a stop,
instead of going on forever.
Explain what is meant by “frame of reference” and provide a situation that illustrates this.
21. One student sees a car and says the car is moving at 29 m/s north, while another student sees
the same car and says the car is not moving. Explain how both students can be correct in their
descriptions of the car.
Solve Vector addition problems within frame of reference.
22. A train is moving at 15 m/s to the right. A person on the train throws a ball at 5.0 m/s to the
right.
o. What speed would the people on the train measure for the thrown ball?
p. What speed would a person standing outside the train measure for the thrown ball?
Section 2.3 Newton’s Second law
Differentiate between mass and weight of an object
23. Explain the difference between mass and weight of an object
24. Explain how can the weight of an object change while the mass remains constant?
Describe Newton’s Second Law
25. According to Newton’s second law, if I want two objects of different mass to have the same
acceleration, which object should receive a stronger force, the more massive or least massive?
Explain using Newton’s 2ns Law.
Use Newton’s second law to calculate mass, acceleration, and force on an object
Calculate the weight, mass, or acceleration due to gravity
26. Determine the mass of the tennis ball that accelerates from rest at 2500 m/s2 when a force of
143 N is applied.
27. Determine the weight of an object with 3 kg of mass if its speed increases downwards -9.81 m/s2
every second when in free fall.
Identify the units used to describe forces
28. What is the equivalent of 1 Newton in terms of kilograms, seconds and meters
29. Explain how could you figure out the equivalence of 1 Newton in terms of kilograms, seconds and
meters by looking at Newton’s Second Law (
= )
Add force vectors acting at right angles or parallel to each other using both the “tip-to-tail” method and
mathematically.
30. Two players on a rugby scrum push against each other. One pushes with 300. N to the right of the
field, and the other with 200. N to the left. What is the net force (include direction)?
31. What is the resultant force on a swimmer that propels herself with 400. N to the north if she is
swimming on a sea current that pushes her with 150. N to the East?
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Sections 4 and 5 Projectile Motion
Describe the difference between free fall and projectile motion
32. What is the difference between free fall and projectile motion?
Draw and describe the position vs time of a projectile and an object in free fall
33. If a projectile is fired horizontally and another is dropped at the same time, which one will hit the
ground first? Draw a diagram to defend your answer and explain your answer in words.
Describe how vertical and horizontal motions are connected in projectile motion.
34. How are the vertical and horizontal motions in of a golf ball in flight related?
Identify the force acting on a projectile
35. What is the only force acting on a football after it is kicked?
Identify the vertical acceleration on a projectile
36. What is the vertical acceleration on a baseball after it has been hit with a bat?
Identify the horizontal acceleration on a projectile
37. What is the horizontal acceleration on a baseball after it has been hit with a bat?
Predict the angle that will provide the maximum range for a projectile when launched from the ground.
38. What angle will produce the maximum range for a projectile?
Resolve velocity of an object into its vertical and horizontal components
39. A football is kicked at 19.5 m/s at an angle of 72o. Determine the horizontal and vertical velocity.
Describe the factors that affect the time a projectile stays in the air .
40. List at least three factors that affect the time a projectile stays in the air
Describe the factors that affect the range of a projectile
41. List two factors that affect the range of a projectile
Know the final vertical velocity at peak and at end of parabolic flight.
42. A golf ball is hit with and initial vertical velocity of 29 m/s. What is the vertical velocity at the
peak of its flight, and the vertical velocity at the end of its parabolic flight?
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Solve mathematical problems on projectile motion including the following:
o
o
o
o
Resolve velocity of an object into its vertical and horizontal components
Use vertical component of motion to find the time the projectile is in the air until:
Maximum height
Overall time
Use time to maximum height to get maximum height reached by projectile
Use horizontal component of velocity and time in the air to find horizontal displacement
(range).
43. A volleyball is bumped straight up at 15 m/s. How long will it take the volleyball to reach its
highest point?
44. A kick ball is kicked at an angle of 23° at 32 m/s.
q. What are the horizontal and vertical components of the initial (net) velocity?
r. What is the time to the maximum height?
s. What is the maximum height reached of the kick ball?
t. What is the time for the entire flight?
u. What is the range of the kick ball?
Sections 2.6 Newton’s 3rd Law
Describe Newton’s 3rd Law
45. Explain what force causes a person on a skateboard to move when the person pushes on a wall.
Explain where does a pair of forces act.
46. Explain how if forces always come in pairs, how can any object be accelerated (experience a net
force)?
Draw Free Body Diagrams
47. Draw the Free Body Diagram on both a soccer player and a soccer ball when the player kicks the
soccer ball to the right. Make sure to label each force you draw in each free body diagram.
Describe physical situations using Newton’s 3rd Law.
48. Describe the force that causes a person to accelerate from a standing position to walking.
Sections 2.7 Friction and Inclined plane
Define friction
49. What is friction
Describe the difference between static and sliding (kinetic) friction
50. What is the difference between static and sliding (kinetic) friction?
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Describe the force normal to the surface
51. Sketch a shoe on a horizontal surface and an inclined surface and then draw in the normal force
acting on the shoe in sketches.
Solve mathematical problems that involve friction including free body diagrams
52. A quarterback of mass 88 kg runs for a first down and then slides to a stop to avoid getting hit.
The coefficient of friction between the ground and the quarterback is known to be 0.45.
v. Draw and clearly label a freebody diagram for the quarterback.
w. Determine the normal force acting on the quarterback.
x. Calculate the force of friction that caused the quarterback to stop.
53. A skier of weight 835 N glides down a constant slope of 7.4°
y. Draw and clearly label a freebody diagram for the skier.
z. Determine the magnitude of the weight force that is parallel to the slope.
aa. Determine the magnitude of the weight force that is perpendicular to the slope.
bb. Determine the coeffiecient of sliding (kinetic) friction for this situation.
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