If almost any system in stable equilibrium is slightly disturbed, it will then exhibit simple harmonic motion because 1. the change in potential energy is proportional to the cube of the displacement from the equilibrium position. 2. the change in potential energy is proportional to the square of the displacement from the equilibrium position. 3. the force on a system in unstable equilibrium is zero. 4. the kinetic energy on a system in stable equilibrium is zero. 5. mechanical energy is conserved. 6. momentum is conserved. 7. the force on a system in stable equilibrium is zero. 8. the momentum of a system in stable equilibrium is zero. 9. momentum and mechanical energy are both conserved. 10. the change in potential energy is proportional to the displacement from the equilibrium position.

The law of conservation of energy states that energy cannot be created or , energy can be from one substance to another. the first blank is ' destroyed ' and for the second blank is ' transferred '

Follow these directions and answer the questions. 1. shine a pencil-thin beam of light on a mirror perpendicular to its surface. (if you don't have a laser light as suggested in the video, you can make a narrow beam from a flashlight by making a cone from black construction paper and taping it over the face of the flashlight.) how does the light reflect? how does the relationship of incident to reflected ray relate to the reflection of water waves moving perpendicular to a barrier? 2. shine a pencil-thin beam of light on a mirror standing on a sheet of paper on the table (or floor) so that you can mark the incident ray and reflected ray. (you can support the mirror from the back by taping it to a wooden block.) 3. mark a line on the paper representing the reflective surface. (the reflective surface of a mirror is usually the back edge.) 4. draw a dashed line perpendicular to the mirror surface at a point where the incident and reflected ray meet. this perpendicular is called a normal to the surface. 5. measure the angles between the rays and the normal. the angle of incidence is the angle formed by the incident ray and the normal to the surface. the angle formed by the reflected ray and normal is called the angle of reflection (r). what is the angle of incidence? what is the angle of reflection? 6. repeat for several different angles. (see report sheet for details.) what appears to be the relationship between the angle of incidence and angle of reflection? in science 1204, what was the relationship for these two angles made by the reflection of waves in a ripple tank? 7. roll a ball bearing so that it hits a fixed, hard surface (a metal plate) at several angles (including head-on). observe the way in which the ball bearing reflects. what generalization can you make about how a ball bearing reflects from a wall? have you proved that light can only behave like a wave?

Which car has the most kinetic energy? a. a car of mass 1000 kg with a speed of 3 m/s b. a car of mass 2000 kg with speed 7 m/s c. a car of mass 1000 kg with speed 7 m/s d. a car of mass 2000 kg with speed 3 m/s