Energy - math word problems

  1. Positional energy
    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?
  2. 3 phase load
    3phasesPower Two wattmeters are connected to measuring power in a 3 phase balanced load. Determine the total power and power factor if the two wattmeters read 1000 watts each (1) both positive and (2) second reading is negative
  3. Kilowatt-hours
    elektricky If the Lewis family used 648 kilowatt-hours of electricity in 12 days, how many kilowatts hours should they use in 24 days at the same rate of usage
  4. Friction coefficient
    car What is the weight of a car when it moves on a horizontal road at a speed of v = 50 km/h at engine power P = 7 kW? The friction coefficient is 0.07
  5. Calories 2
    energy_2 Ben eats approximately 2400 calories per day. His wife Sarah eats 5/8 as much. How many calories does Sarah eat per day?
  6. Gasoline price
    fuel_pump2_1 At 34.4 cents per liter, how much will 42 liters of gasoline cost?
  7. The tub
    teplomer_18 If we drop the 5 l from the first tap and the from second 2 liters of water, the water in the tub will have a temperature of 25°C. If we drop 3 l from the first tap and from second 4 l of water, the water in the tub will have a temperature of 21°C. Determi
  8. Orlík hydroelectric plant
    1280px-Orlík_1 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
  9. Electric input power
    resistor_7 Solve problems related to electric power: a) U = 120 V, I = 0.5 A, P =? b) P = 200 W, U = 230 V, I =? c) I = 5 A, P = 2200W, U =?
  10. Bulbs
    bulbs_2 There are 875 identical light bulbs in the sports hall lightning for 2 hours. How long does it lightning 100 this light bulbs?
  11. Electric energy
    bulb _3 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?
  12. Bulb
    bulb _2 A 60 W bulb consumes 0.12 kWh of electricity. How long did she stand light without a break?
  13. Natural gas in kWh
    plynomer Gas consumption for 2017 was 11,301 kWh I paid 532 € How much 1 m3?
  14. Filament of bulb
    bulb _1 The filament of bulb has a 1 ohm resistivity and is connected to a voltage 220 V. How much electric charge will pass through the fiber when the electric current passes for 10 seconds?
  15. Calories
    fries A large order of McDonald’s french fries has 500 calories. Of this total, 220 calories are from fat. Find the ratio of the calories from fat to total calories in a large order of McDonald’s french fries.
  16. Ounce
    energy_1 749 calories in a 7 - ounce serving . What is the unit rate?
  17. Chocolate roll
    chocholate_3 The cube of 5 cm chocolate roll weighs 30 g. How many calories will contain the same chocolate roller of a prism shape with a length of 0.5 m whose cross section is an isosceles trapezoid with bases 25 and 13 cm and legs 10 cm. You know that 100 g of this.
  18. Efficiency
    rychlovarna-kanvica What is the power output of kettle 2 kW with efficiency 90%?
  19. 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.
  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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