Energy - examples

  1. Excavation
    vykop_ryha Mr. Radoslav calculated that excavation for a water connection dig for 10 days. His friend would take 7 days. Radoslav worked 3 days alone. Then his friend came to help and started on the other end. On what day since the beginning of excavation they met?
  2. Cubic
    natural_gas Convert 1647 m3 of natural gas volume to energy units kWh. Combustion of 1 cubic meter of natural gas is released energy 10.55 kWh.
  3. MPG
    mpg 181 miles a week fills up twice a week. Each fill is 31 gallons. What is gas mileage of the car?
  4. Efficiency
    rychlovarna-kanvica What is the power output of kettle 2 kW with efficiency 90%?
  5. Three drivers
    gas_car Three driversdriving the same direction found that they have same amounth of gasoline. The first is enough to go 6 km, 4 km second and third 3km. Gasoline they divided so all three just drove to the nearest petrol station. How many km away was a petrol sta
  6. Bath
    bathroom In the bath is 30 liters of hot water. Then added 38 liters of cold water at temperature of 17 °C decreased temperature of water to 48 °C. What was the initial temperature of the hot water?
  7. Motor physics
    car_motor Car traveling at 97 km/h on the highway. Pulling power of the motor is 6 kN. Determine engine power in kW.
  8. Rates
    gas_meter When gas consumption, the consumer may choose one of two rates: rate A - which pays 0.35 € per 1 m3 of gas a flat monthly fee of 3.6 € (regardless of consumption) rate B - which pays 0.295 € per 1 m3 of gas a flat monthly fee of 8.3 € From what monthl
  9. Gasoline consumption Skoda MB
    Skoda_120 Consumption of cars for 100 km is 6.6 liters of gasoline 1 liter of gasoline costs € 1.274. How many euro grandfather spent when the car travelled 321 km.
  10. Elevator
    vytah-sachta In homes with more floor elevators are used. For passenger transport, the most commonly used traction elevator counterweight. The top of the shaft engine room with the engine. The car is suspended on a rope, which is guided up over two pulleys to the count
  11. Engineer Kažimír
    demagog_smer_1 The difference between politicians-demagogues and reasonable person with at least primary education beautifully illustrated by the TV show example. "Engineer" Kažimír says that during their tenure there was a large decline in the price of natural gas, pri
  12. Cows
    kravy0 20 cows has food for 60 days. We reduce the dose to two-thirds for 18 cows. How many days will be fed?
  13. Locomotive
    locomotive_1 Locomotive pulled a train permanent load of 200 kN horizontally along the track of 5km. What work it done?
  14. Stand-by power
    remote_control Determine the year-round consumption of appliances in stand-by mode. Stand-by mode is regime the unit continuously 24 hours consume a tiny amount of electricity. Typically are televisions, electric ovens, radios, computers, monitors, satellite receivers, w
  15. Decibel
    db A circuit has an input power of 72 mW. Its output power is 9 mW. What is the loss in decibels?
  16. Pump
    pumpa What power has a pump output to move 4502 hl of water to a height of 32 m for 5 hours?
  17. Fuel mileage
    fuel2 You have 3/8 tank of fuel. Estimate fuel consumption @ 6mpg. Estimate speed @ 50mph. Your fuel tank holds 200 gals. Figure out fuel mileage.
  18. Shot
    wood_projectile Shot with a mass 21 g flying at 508 m/s penetrates into the wood to a depth 19 cm. What is the average force of resistance of wood?
  19. Ounce
    energy_1 749 calories in a 7 - ounce serving . What is the unit rate?
  20. Energy
    energy In one region, the September energy consumption levels for single-family homes are found to be normally distributed with a mean of 1050 kWh and a standard deviation of of 218 kWh. Find the consumption level separating the bottom 45% from the top 55%.

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