# Physical Science

## Chapter 4: Energy

### Energy

 1. The __________ is the SI unit of energy. Need a Hint? A) joule B) volt C) ampere D) watt 2. By what process does the Sun produce enough energy to warm Earth? Need a Hint? A) nuclear fusion B) glycolysis C) catabolism D) transformation of thermal energy into kinetic energy 3. What two factors determine how much gravitational potential energy is in an object? Need a Hint? A) weight and speed of the object B) weight of the object and height above the ground C) shape and speed of the object D) shape of the object and its position relative to the ground 4. Which of the following vehicles has the most kinetic energy? Need a Hint? A) a 900-kg car traveling 80 km/h B) a 1,100-kg car traveling 60 km/h C) a 2000-kg truck traveling 50 km/h D) a 300-kg motorcycle traveling 100 km/h 5. A baseball is hit into the air with a bat. When does the baseball have the greatest gravitational potential energy? Need a Hint? A) when it leaves the bat B) when it reaches its highest point C) when it hits the ground D) when the mechanical and kinetic energies of the baseball are equal 6. What two factors determine how much potential energy an object has? Need a Hint? A) mass and position B) speed and mass C) speed and surface area D) speed and position 7. The law of conservation of energy states that __________. Need a Hint? A) energy is not created or destroyed and its form is constant B) energy cannot be created or destroyed C) when energy is transformed, the total energy of a system is less than it was before the change D) energy can be created and destroyed but cannot change form 8. As energy transformations occur within a system, the total energy of the system __________. Need a Hint? A) decreases B) is transferred out of the system C) increases D) remains constant 9. During energy transformations, energy is never __________. Need a Hint? A) used to increase an object's potential energy B) created or destroyed C) released as heat D) completely transformed 10. Which of the following statements about an apple falling from a tree is true? Need a Hint? A) Its kinetic and potential energies remain constant. B) Its kinetic energy decreases and its potential energy increases. C) Its potential energy decreases and its kinetic energy increases. D) Its mechanical energy increases. 11. __________ is the energy stored in an object due to its position. Need a Hint? A) Potential energy B) Entropy C) Thermal energy D) Kinetic energy 12. What is a joule? Need a Hint? A) the unit of measurement describing the change in velocity in a unit time B) a unit of energy that depends on both an object's mass and velocity C) a unit measuring the amount of energy we get from various foods D) the unit of force required to move 1 kg of mass 1 m/s/s 13. How much gravitational potential energy does a 75-kg diver have stepping off the edge of a 5-m platform? Need a Hint? A) 147 J B) 15 J C) 3,675 J D) 375 J 14. __________ is energy stored by things that stretch or compress. Need a Hint? A) Elastic kinetic energy B) Chemical kinetic energy C) Gravitational potential D) Elastic potential energy 15. Which of the following objects has potential energy? Need a Hint? A) a ball rolling across the floor B) a bowling ball knocking over a pin C) a glass sitting on a table D) a bicycle coasting down a hill 16. Without changing the mass of a moving object, doubling its velocity will __________ its kinetic energy. Need a Hint? A) triple B) not affect C) double D) quadruple 17. How much kinetic energy does a moving object have if its mass is 100 kg and it is moving at a speed of 5 meters per second? Need a Hint? A) 250 J B) 1,250 J C) 2,500 J D) 125,000 J 18. Carbohydrates and proteins each supply about __________ Calories of energy per gram. Need a Hint? A) 40 B) 400 C) 4 D) 14 19. What two factors determine how much kinetic energy an object has? Need a Hint? A) position and mass B) speed and surface area C) speed and mass D) speed and position 20. One food Calorie is equivalent to approximately __________. Need a Hint? A) 4 J B) 400 J C) 40 J D) 4,000 J