Physics! The force is with (name) First Semester Exam Review Topics, Objectives, and Sample questions

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1 Physics! The force is with (name) First Semester Exam Review Topics, Objectives, and Sample questions The day of the final: The final exam will be multiple-choice and short answer. You may only use your own pencil and calculator (or one that has been lent to you alone for this exam.) Be prepared to show all work, including units, to receive credit (on the short answer portion). Remember: be sure to read all the problems and to follow all directions. You will have more than enough time to finish the test, but be careful not to spend all of your time on one problem. Other friendly reminders Do not bring electronic devices to the exam (other than a non-graphing calculator). This includes cell phones and mp3 players. If I see them I will take them. No headphones! There will be no rest room passes until you are done with the test. You may make your own help sheet, both sides of a 40cm 2 (maximum area) note card of formulas, definitions, and helpful hints and steps. NO EXAMPLES. This will be collected after the final. Remember that numbers alone or single word answers don t show that you understand, but thoughtful explanations can.

2 Objectives Here is a list of the objectives you have been meeting during the semester. These will be assessed on the final exam. Constant Velocity Particle Model (CVPM) I can draw and interpret diagrams to represent the motion of an object moving with a constant velocity. I can solve problems using the constant velocity particle model. Constant/Uniform Acceleration Particle Model (CAPM) I can draw and interpret diagrams to represent the motion of an object moving with a changing velocity. I can describe the motion of an object in words using the velocity-vs-time graph. I can solve problems using kinematics concepts. Balanced Forces Particle Model (BFPM) I draw properly labeled free body diagrams that show all forces acting on an object. When given one force, I can identify and describe its N3L pair. I related balanced/unbalanced forces to an object s constant/changing motion. I can use N1L to quantitatively determine the forces acting on an object moving at a constant velocity. Unbalanced Forces (Net Force) Particle Model (UbFPM) I use multiple diagrams and graphs to represent objects moving at a changing velocity. My free-body-diagrams look qualitatively accurate (balanced or unbalanced in the correct directions, relative size of forces). I can solve problems using Newton s 2 nd Law. Topics for first semester physics final. FALL 2014 Be prepared to answer questions and solve problems based on the following ideas: (Review problem-solving procedure.) Scientific methods - Experimental procedure: Independent, dependent and controlled variables. - Graphical representation of data. - Mathematical representation of data. (slope, y-intercept, linearizing graphs, equation of line w/ variables) Constant Velocity Particle Model - Graphical, mathematical and diagrammatical representations of constant velocity. - Motion maps, velocity vectors - Average speed -Free fall Uniform Acceleration Particle Model - Graphical, mathematical and diagrammatical representations of constant acceleration. - Interpretation of slopes and area under kinematics graphs. - Instantaneous velocity vs. average velocity - Vectors vs. Scalars

3 Balanced Force Particle model - Graphical, mathematical and diagrammatical representations of a free particle. - Newton's first law (inertia) - Newton's third law (interaction) - Force diagrams (lengths, direction, labels, kinds of interaction) - Vectors: components, (trig!) vector addition, and equilibrium - Mass vs. weight Unbalanced (Net force) particle model - Graphical, mathematical and diagrammatical representations for a particle experiencing a constant force. (some examples include but not limited to: elevators, modified atwood machine (like our lab), particle down a slope, or along a level plane). - Newton's second law: Net force = mass of system x system acceleration -Calculating the frictional force or mu (µ). Semester 1 Physics Review Questions Note: This is not a comprehensive list! These are additional practice questions for your personal amusement. 1. A car cruising at 20 m/s decelerates at 1.7 m/s 2 for 5 seconds. Draw a motion map. What is the car's final velocity? 2. A car traveling west has a speed of 25 m/s. A car traveling east has a speed of 25 m/s. Are their velocities equal? Explain. 3. Compare and contrast vectors and scalars. Give examples of each..

4 4. A baseball is thrown vertically upward into the air and returns to its starting point. Sketch its position vs. time, velocity vs. time and acceleration vs. time graphs. 5. A ball thrown vertically upward is caught by the thrower after 20 s. Find (a) the initial velocity of the ball and (b) the ball's velocity 5 seconds after it is thrown, (c) the maximum height the ball reaches, (d) the acceleration of the ball at the top. 6. A jet plane lands with a velocity of 100 m/s and can decelerate at a maximum rate of 5 m/s 2 as it comes to rest. (a) From the instant it touches the runway, what is the minimum time needed before it can come to rest? (b) Can this plane land on a small island airport where the runway is 0.8 km long? 7. A cheap, junky domestic car is capable of accelerating at a rate of 0.6 m/s 2. How long does it take for this car to go from a speed of 55 mi/hr to 60 mi/hr? (Careful with units.)

5 8. A speedy tortoise can run with a speed of 10 cm/s, and a hare can run 20 times as fast. In a race, they both start at the same time, but the hare stops to rest for 2.0 minutes and the tortoise wins by a shell (20 cm). (a) How long does the race take? (b) What is the length of the race? (c) Draw a quantitative position-time graph of the race. 9. The tallest volcano in the Solar System is the 24-km tall Martian volcano, Olympus Mons. A future astronaut drops a ball off the rim of the crater and the ball falls 24 km with a constant acceleration of 3.7 m/s 2. (We assume that the volcanic crater is as deep as the volcano is tall, which is not actually true.) Find (a) the time for the ball to reach the crater floor and (b) the velocity with which it hits. (In light of your answer for the velocity, does it seem that air resistance, even in Mars' thin atmosphere, can really be neglected in this problem?) 10. In one scene of a Bugs Bunny cartoon, we find Bugs standing on a large flat rock as both he and the rock fall through the air under gravity. Just before impact with the ground, Bugs Bunny steps off the rock and walks away, completely unharmed; the rock is totally destroyed. In terms of Newton's first law of motion, why is this scene unrealistic?

6 11. Draw a quantitative force diagram for a 6 kg final exam at rest on a desk rakishly tilted at 15 o. 12. A horse exerts a 500 N force on a heavy wagon, causing it to accelerate. What force does the wagon exert on the horse? (a) less than 500 N (b) 500 N (c) more than 500 N (d) it s not possible to tell Briefly explain your reasoning:

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