Physical Science Unit Exam Review. Date Period

Transcription

1 1. Give an example of gravitational potential energy. Frog at the top of its jump Rock at the edge of a hill Skateboarder at the top of the ramp Pendulum at the top of its swing 2. Use Newton s 2 nd law to solve for the mass of the object: Force = 10N Acceleration = 2 m/s/s F = MXA 10 N = M x 2 m/s/s 10N/2m/s/s M= 5 Kg 3. If the net force acting upon an object is greater than 0 N, then is the object accelerating? Why or why not? UNBALANCED so the object has to either be speeding or slowing down 4. Is this object in the graph balanced, unbalanced, or moving in a constant velocity? BALANCED and MOVING AT A CONSTANT VELOCITY 5. Is this object in the graph balanced, unbalanced, or moving at a constant velocity? UNBALANCED SLOWING DOWN (NEGATIVE ACCELERATION)

2 6. What is the net force in the diagram? NET FORCE = = 200N down 7. How does a wind turbine transform energy? WIND ENERGY MECHANICAL ENERGY ELECTRICAL ENERGY 8. Wind, solar, geothermal and hydroelectric are all examples of what type of energy? GREEN ENERGY 9. What type of energy transfer would occur with a person running a marathon? CHEMICAL ENERGY MECHANICAL ENERGY 10. What is the energy transformation of a frog jumping from the ground and reaching its highest point? ELASTIC POTENTIAL ENERGY KINETIC ENERGY GRAVITATIONAL POTENTIAL ENERGY 11. Give an example of work in the scientific sense. WORK = FORCE X DISTANCE WORK IS DONE WHEN A FORCE IS APPLIED TO AN OBJECT AND IT MOVES A DISTANCE EX: - PERSON LIFTING A CHAIR OVER THEIR HEAD - A PERSON WRITING (PUSHING THE PEN/PENCIL)

3 - A PERSON MOWING THE LAWN WITH A PUSH MOWER - A PERSON PUSHING A STROLLER 12. A ramp in a building is an example of which simple machine? INCLINED PLANE 13. On what point does a lever pivot? FULCRUM 14. How do simple machines make work easier? TO MAKE WORK EASIER BY: -TRANSFERRING A FORCE -CHANGING THE DIRECTION OF A FORCE -INCREASING THE MAGNITUDE -INCREASING DISTANCE OR SPEED 15. The efficiency of a simple machine is always because of. LESS THAN 100% DUE TO FRICTION 16. Roller skates are an example of what type of simple machine? WHEEL AND AXLE 17. The bottom of a light bulb is an example of what type of simple machine? SCREW 18. If the output force is greater than the input force when using a simple machine, what is achieved? MECHANICAL ADVANTAGE 19. If you kick a bowling ball and a tennis ball with the same amount of force, what will happen according to Newton s second law of motion? THE TENNIS BALL WILL GO FURTHER BECAUSE IT S MASS IS LESS SO ITS ACCELERATION INCREASES

4 20. Reactions always go in the direction of the action. OPPOSITE 21. Use Newton s 2 nd law to solve for the force exerted on an object: Mass = 10Kg Acceleration = 2 m/s/s F = MXA F = 10 Kg x 2 m/s/s F= 20 N 22. What is an example of an outside force that slows down a moving object? FRICTION 23. What is inertia? AN OBJECT IN MOTION WILL STAY IN MOTION AND AN OBJECT AT REST WILL STAY AT REST 24. What is velocity? SPEED IN A GIVEN DIRECTION 25. Draw a distance/time graph that shows an increase in speed. Distance Time

5 26. Draw an example of a series circuit. 27. Because Christmas bulbs are wired in a series circuit, what happens if one bulb goes out? ALL OF THE LIGHTS WILL GO OUT 28. What device is used to open and close a circuit? SWITCH 29. Draw an example of a closed circuit with a battery, lightbulb, and wire indicating that the bulb will light up.

6 30. Give an example of Newton s 1 st Law of Motion in real life. - PENCIL SITTING ON A TABLE UNTIL SOMEONE PICKS IT UP - A CAR MOVING AT A CONSTANT VELOCITY - HITTING GOLF BALL GOLF BALL WOULD CONTINUE TO FLY - EARTH REVOLVING AROUND THE SUN OR ROTATING - SLAMMING ON THE BREAKS CAUSES PEOPLE IN THE CAR TO MOVE FORWARD AT THE SAME VELOCITY - KICKING A SOCCER BALL WOULD CAUSE THE SOCCER BALL TO CONTINUE TO MOVE AT A CONSTANT VELOCITY 31. Give an example of Newton s 2 nd Law of Motion in real life. - DROPPING A HAMMER AND A PENNY AT THE SAME TIME HAMMER HITS WITH A GREATER FORCE - KICKING A TENNIS AND BOWLING BALL WITH THE SAME FORCES CAUSES THE TENNIS BALL TO GO FURTHER 32. Give an example of Newton s 3 rd Law of Motion in real life. - FISH SWIMMING THROUGH WATER (PUSHES BACK ON WATER WITH FINS, FISH MOVES FORWARD IN THE WATER - BIRD FLYING THROUGH THE AIR (BIRD PUSHES DOWN ON AIR, BIRD MOVES UP) - SHOOTING A BULLET FROM A GUN (EXPLOSION PUSHES BACKWARDS, BULLET FLIES FORWARD) - THROWING A TENNIS BALL AT THE WALL (TENNIS BALL FLYS FORWARD, HITS THE WALL, AND COMES BACK IN THE OPPOSITE DIRECTION)

7 33. Give an example for each of the following energy transformations: a. Electrical to thermal TOASTER, TANNING BED, HEATER, IRON b. Chemical to electrical CALCULATOR, CELL PHONES c. Chemical to mechanical CORDLESS DRILL, BATTERY OPERATED TOY DOG, REMOTE CONTROLLED CAR, RUNNING d. Gravitational potential to kinetic FROG AT THE TOP OF ITS JUMP COMING DOWN ROLER COASTER AT THE TOP OF THE HILL GOING DOWN SKIER AT THE TOP OF THE HILL e. Electrical to radiant LAMP TELEVISION MICROWAVE projector