Name: _______________________

Date:______ Period:______

1. If it requires a steady force of 150 newtons to pull a boat, how much work is required to pull a boat 8 meters? Given: Force = 150 newtons Distance = 8 meters Find: Work Known: Work (W) = force x distance 1 newton-meter = 1 joule (J) Solution: 2. It requires 500 joules of energy and 100 newtons of force to move an object from point A to point B. What is the distance between point A and point B? Given: Energy = 500 joules Force = 100 newtons Find: Distance Known: W = force x distance and by rearranging Distance = W Force 1 newton-meter = 1 joule Solution: 3. How much energy is required to produce 460 joules of light energy from a light bulb that is 25 percent efficient? Given: % eff. = 2.5 Energy out = 460 Find: Energy in Known: % eff.= Wout x 100 Win By rearranging: Wout x 100 Win = % eff Solution: 4. What is the efficiency of a light bulb that uses 1000 joules of electric energy to produce 200 joules of light energy? Given: Energy in = 100 joules

Energy out = 200 joules Find: Percent efficiency Known: % eff.= Wout x 100 Win Solution: 5. What is the efficiency of an electric generator that produces 5000 joules of electric energy from the 7000 joules of mechanical energy used to rotate the generator? Given: Energy in = 7000 joules Energy out = 5000 joules Find: Percent efficiency Known: % eff.= Wout x 100 Win Solution: 6. If it requires a steady force of 6000 newtons to pull a car, how much work is required to pull a car 50 meters? Given: Find: Known: Solution: 7. It requires 200 joules of energy and 25 newtons of force to move Mr. Scott from A hall to D hall. What is the distance between A hall and D hall? Given: Find: Known: Solution: 8. What is the efficiency of a television that uses 7000 joules of electric energy to produce 500 joules of light energy? Given: Find: Known: Solution: 9. How much energy is required to produce 900 joules of wind energy from a wind

turbine that is 62 percent efficient? Given: Find: Known: Solution: 10. What is the efficiency of a wind turbine that produces 11000 joules of wind energy from the 13000 joules of mechanical energy used to rotate the turbine? Given: Find: Known: Solution:

ch_1_math_problems

Distance = 8 meters Given: Energy = 500 joules 1 newton-meter = 1 joule point A to point B. What is the distance between point A and point B...

ch_1_math_problems

Distance = 8 meters Given: Energy = 500 joules 1 newton-meter = 1 joule point A to point B. What is the distance between point A and point B...