Final Exam Study guide 2024.pdf

NCCS 8th Grade Science Name:_____________________ Mr. Maliakal Physics Exam Study Guide Terms / Concepts: Vector vs. Scalar Quantity (examples of each) Motion Frame of Reference Distance vs. Displacement Speed vs. Velocity...

NCCS 8th Grade Science Name:_____________________ Mr. Maliakal Physics Exam Study Guide Terms / Concepts: Vector vs. Scalar Quantity (examples of each) Motion Frame of Reference Distance vs. Displacement Speed vs. Velocity Instantaneous Speed vs. Average Speed Distance vs. Time Graphs (what does the slope equal - be able to interpret) Acceleration Velocity vs. time graph (what does slope equal – be able to interpret) Acceleration due to gravity (g) S.I. units for distance, speed, velocity and acceleration Force Combining forces (balanced and unbalanced situations, net force) Friction (static, sliding and rolling, fluid) Gravity Lift Drag Projectile Motion Newton’s first law of motion (inertia) Newton’s second law of motion Newton’s third law of motion Weight Momentum Pressure Bernoulli’s principle Buoyancy and buoyancy force Archimedes’ Principle Work Power Machine Input force Input distance Output force Output distance Work input Work output Inclined Plane (Ramp) Wedge Screw Pulley (fixed and moveable, pulley systems) Levers (first, second and third class) Wheel and axel Compound Machine Formulas: Know the formulas for the following Average velocity or speed Average acceleration Acceleration (calculated from force and mass – Newton’s Second Law) Weight (calculated from mass and acceleration) Momentum Pressure Work Power Work Input(Wi) Work output(Wo) FiDi = FoDo (assuming no friction); in reality, Work input > Work output due to friction Review Questions: 1. On the graph below, during what time interval is the velocity the highest? During what interval is the object at rest? Circle the portion(s) of the curve where you think the object is accelerating. Put a “*” on the portion of the curve where you think it is decelerating. Distance vs. Time of an Object on a Track ance Dist (m) A B Time (S) C 2. A girl walks 200m N, then 300m W then 150m N, then 200m E, then 100m N, then 100m E. What is the distance that she walked? Use arrow to sketch a vector diagram of her route. What is her displacement? 3. A cyclist is riding along Ponus Ridge road traveling at 8m/s. A car passes her traveling in the same direction at 15m/s. From the frame of reference of the cyclist, how fast does the car appear to be traveling? From the frame of reference of a person standing on the side of the road, how fast does the car appear to be traveling? 4. A people mover at JFK airport is moving east at 1.5m/s. A naughty boy running west a 4m/s runs onto the people mover in the wrong direction. What is his velocity relative to a person standing on the carpeted floor adjacent to the people mover? 5. Covert the following: 0.56km to m 346cm to m 1550m to km 6. A car begins traveling after being stopped at a red light. After 30seconds, its velocity is west at 15m/s. It then maintains that velocity for 2 minutes, at which point it begins to slow down and eventually come to a stop at another red light. At what point is the car accelerating? At what point is it decelerating? Is there any point when acceleration is equal to zero? 7. A runner in an 800 meter race runs the first 400.0m in 45.3seconds, but then quickens her pace during the second 400.0 meters, completing the second 400.0 m in 42.1seconds. Calculate the average speed for the first and second 400.0 meters, and the average speed for the entire race. (Show all work) 8. A velocity vs. time graph of a car traveling down the street appears as a straight line sloping upwards. What can you infer about the acceleration of the car during the time frame depicted by the graph? 9. A jaguar charges at a peccary (a wild pig) foraging for seeds under the forest canopy. After 3.0 seconds, it is traveling at a speed of 10.3m/s. What was the average acceleration over this charge? (Show all work) 10. At what speed will a marble dropped from the top of a building be traveling at after 2.2 seconds? (Show all work) 11. Speed vs. Time for a Car on a Short Trip Speed (m/s) Time Circle the portion(s) of the graph above where the car is accelerating. Circle the portion(s) where it is decelerating. Circle where its acceleration is zero. 12. True or False: If acceleration is zero, velocity must also be zero. 13. True or False: If the velocity of an airplane is constant over a 1 minute period, its instantaneous velocity at any point during the time frame is equal to its average velocity over the 1 minute time period. 14.What is a force? How might a force accelerate an object that is already in motion? 15) Which of the following is not a force: a) friction b) gravity c) momentum d) weight 16) You push a box and are unable to move it. What force opposes your push? 17) What force besides gravity acts on a projectile? 18) How is mass different than weight? How might the weight of an object change while it’s mass remains constant? 19) What two things does momentum depend on? 20) What has more momentum, a 3.5g marble rolling across the floor at a speed of 4.5m/s, or a stationary bowling ball? Show work. 21) When the forces acting on an object are balanced, the net force is equal to… 22) Rank the following types of friction from highest force to lowest force for a given set of materials. a) rolling b) static c) sliding 23) What is the rate of acceleration of an object in free fall? Why do objects in free fall eventually start traveling at a constant velocity? What is the velocity called? 24) You watch with amazement as someone is able to pull a table cloth out from underneath a plate, glass and silverware. Explain why this is possible. Be sure to mention which of Newton’s laws accounts for this. 25) Which of Newton’s laws explains why it is easier to push an empty shopping cart as opposed to a full one? Explain. 26) A 0.2 kg baseball is thrown with a force of 30N. What is its acceleration? (show work) 27) A WWF wrestler has a mass of 157 kg. Calculate his weight in newtons. (show work) 28) Which has more momentum, a 4.7 g bullet shot from a gun at 1600 m/s or baseball with a mass of 150g thrown at 39m/s? 29) Identify the action and reaction forces in each of the following examples: a) a balloon car b) swimmer 30) What does Bernoulli’s principle state? 31) Be able to explain the following demonstrations:  Airplane wing in front of fan Pingpong ball held up by blow dryer Bernoulli airbrush Egg pushed into a flask 32) What is buoyancy force? 33) What does Archimedes’ Principle State? 34) How does buoyancy force compare to weight in each of the following situations: a) when an object sinks b) when an object is suspended c) when an object is floating d) when an object is rising (ie. Helium balloon that is released) 35) Explain how it is possible for a ship made of steel (a material far more dense than water) to float. 36) A student lifts a book that weighs 20N, 0.7m to place it on a book shelf. How much work did the student do? 37) Jenny exerts a force of 30N to hold a picture steady as her mommy hangs it on the wall. How much work does she do? 38) Jacko and his friend Danny have a bicycle race to the top of a hill that is 150m in elevation. Jacko weighs 550N and Danny weighs 600N. They use identical bikes that each weigh 30N. Jacko reaches the top of the hill in 20seconds while it takes Danny 21seconds. How much work does each person due? What is the power output of each rider in Watts? 39) If output distance of a machine is greater than the input distance, how does the input force compare to the output force? Give an example of a machine where this is the case. 40) If the input force of the machine is less than the output force, how does the input distance compare to the output distance? Give an example of machine where this is the case. 41) A fixed pulley at the top of a flag pole is used to raise a large flag with a weight of 25N. How much force will need to be applied to the rope? (Assume no friction) 42) A person exerts a force of 3.7N over a distance of.8cm as they pull up on a soda can tab to open a can of soda. The other end of the tab pushes down a distance of.1cm to open the can. What force does it exert to open the can? 43) A rower pulls an oar a distance of 1.1m as she rows a boat. The end of the oar with the paddle blade exerts a force of 10.5N against the water for a distance of 2.7m. What force doe the rower apply to the oar as she pulls it? 44) Identify what type of simple machine each of the following objects are. For levers, indicate the class. If it is a compound machine, identify the simple machines that make it up. a) wheel chair ramp b) nutcracker c) see saw d) bolt e) door knob f) baseball bat g) rake h) crowbar i) nail j) car steering wheel k) screw driver l) scissors m) wrench n) ax o) soda can tab p) pliers q) a hammer r) bottle opener s) pull up blinds t) an uphill section of a road