# Energy - examples

- Excavation

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? - Cubic

Convert 1647 m^{3}of natural gas volume to energy units kWh. Combustion of 1 cubic meter of natural gas is released energy 10.55 kWh. - MPG

181 miles a week fills up twice a week. Each fill is 31 gallons. What is gas mileage of the car? - Efficiency

What is the power output of kettle 2 kW with efficiency 90%? - Bath

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? - Three drivers

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 - Rates

When gas consumption, the consumer may choose one of two rates: rate A - which pays 0.35 € per 1 m^{3}of gas a flat monthly fee of 3.6 € (regardless of consumption) rate B - which pays 0.295 € per 1 m^{3}of gas a flat monthly fee of 8.3 € From what monthl - Motor physics

Car traveling at 97 km/h on the highway. Pulling power of the motor is 6 kN. Determine engine power in kW. - Gasoline consumption Skoda MB

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. - Elevator

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 - Engineer Kažimír

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 - Cows

20 cows has food for 60 days. We reduce the dose to two-thirds for 18 cows. How many days will be fed? - Stand-by power

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 - Pump

What power has a pump output to move 4502 hl of water to a height of 32 m for 5 hours? - Shot

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? - Decibel

A circuit has an input power of 72 mW. Its output power is 9 mW. What is the loss in decibels? - Fuel mileage

You have 3/8 tank of fuel. Estimate fuel consumption @ 6mpg. Estimate speed @ 50mph. Your fuel tank holds 200 gals. Figure out fuel mileage. - 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%. - Locomotive

Locomotive pulled a train permanent load of 200 kN horizontally along the track of 5km. What work it done? - Car

At what horizontal distance reaches the car weight m = 864 kg speed v = 72 km/h when the car engine develops a tensile force F = 2313 N. (Neglect resistance of the environment.)

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