# Energy - math word problems

#### Number of problems found: 51

• Positional energy What velocity in km/h must a body weighing 60 kg have for its kinetic energy to be the same as its positional energy at the height 50 m?
• 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%.
• Cubic Convert 660 m3 of natural gas volume to energy units kWh. Combustion of 1 cubic meter of natural gas is released energy 10.55 kWh.
• Energy saving They were released three different, independent inventions saving 12%, 15% and 25% energy. Some considered that while the use of these inventions, the total savings will be 12% + 15% + 25% = 52%. Is this true? How much percent of energy will save all thre
• Energy consumption The device is connected to 230V and draws 3.5A current. Power consumption is 1932kJ. How many minutes has this device been in operation?
• Harmonic oscillator Calculate the total energy of a body performing a harmonic oscillating motion if its mass is 200 g, the amplitude of the deflection is 2 cm and the frequency is 5 Hz. Round the result to 3 decimal places.
• Electric energy There are 875 identical light bulbs in the sports hall lighting for 2 hours. How long does the same amount of electricity consume 100 such bulbs?
• Orlík hydroelectric plant The Orlík hydroelectric power plant, built in 1954-1961, consists of four Kaplan turbines. For each of them, the water with a flow rate of Q = 150 m3/s is supplied with a flow rate of h = 70.5 m at full power. a) What is the total installed power of the p
• Gasoline price At 34.4 cents per liter, how much will 42 liters of gasoline cost?
• Bulb A 60 W bulb consumes 0.12 kWh of electricity. How long did she stand light without a break?
• Locomotive Locomotive pulled a train permanent load of 200 kN horizontally along the track of 5km. What work it done?
• MPG 252 miles a week fills up twice a week. Each fill is 38 gallons. What is gas mileage of the car?
• 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
• Ounce 749 calories in a 7 - ounce serving . What is the unit rate?
• Efficiency What is the power output of kettle 2 kW with efficiency 90%?
• Decibel A circuit has an input power of 58 mW. Its output power is 6 mW. What is the loss in decibels?
• Cooker A current of 2A passes through the immersion cooker at a voltage of 230V. What work do the electric field forces in 2 minutes?
• Natural gas in kWh Gas consumption for 2017 was 11,301 kWh I paid 532 € How much 1 m3?
• Receiving heat How many degrees Celsius was an iron cylinder weighing 300 g heated in a water bath if it received heat of 7.2 kJ? (specific heat capacity of iron c = 0.46kJ/kg / ºC)
• Cows 20 cows has food for 60 days. We reduce the dose to two-thirds for 18 cows. How many days will be fed?

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