Mass + power - math problems

Number of problems found: 19

  • Density 2
    woord What is the density of a piece of driftwood that has the mass of 25 grams and a volume is 30 cm to the 3rd power. And how do I figure it out?
  • 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
  • Pump
    pumpa What power has a pump output to move 4853 hl of water to a height of 31 m for 8 hours?
  • Electric cooker
     electric cooker During which time t does an electric cooker with power input P = 500 W and with efficiency n = 75% heat water with mass m = 2 kg and temperature t1 = 10°C to the boiling point (t2 = 100°C). The specific heat capacity of water is c = 4 180 J. Kg-1. K-1
  • 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 coun
  • Concrete column
    beton The concrete column of the highway bridge has the shape of a block with dimensions of 1m x 0.8m x 25m. It should be lifted by crane to a height of 20m. What is the power of his engine if the lifting takes 2 minutes?
  • Cube
    kocka_rubik The cube weighs 11 kg. How weight is a cube of the same material if its dimensions are 3-times smaller?
  • 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
  • Hollow sphere
    Xmas_ball Calculate the weight of a hollow stříbrné sphere (density 10.5 g/cm3) if the vnitřní diameter is 15 cm and wall thickness is 1 mm.
  • Granite cube
    cube_3 What is the weight in kg granite cube with an edge of 0.5 m if 1dm3 of granite weight 2600 g?
  • Sphere
    1sphere The surface of the sphere is 12100 cm2, and the weight is 136 kg. What is its density?
  • The half life
    exp_growth2 The half-life of a radioactive isotope is the time it takes for a quantity of the isotope to be reduced to half its initial mass. Starting with 145 grams of a radioactive isotope, how much will be left after 3 half-lives?
  • A car
    car_31 A car weighing 1.05 tonnes driving at the maximum allowed speed in the village (50 km/h) hit a solid concrete bulkhead. Calculate height it would have to fall on the concrete surface to make the impact intensity the same as in the first case!
  • Iron sphere
    sphere_1 Iron sphere has weight 100 kg and density ρ = 7600 kg/m3. Calculate the volume, surface and diameter of the sphere.
  • Wall thickness
    sphere_Nickel The hollow metal ball has an outside diameter of 40 cm. Determine the wall thickness if the weight is 25 kg and the metal density is 8.45 g/cm3.
  • BMI index
    man_BMI Calculate BMI (body mass index, an index indicating obesity, overweight, normal weight, underweight) man weighing m = 71 kg and height h = 170 cm. The index is calculated according to equation (formula): ? With BMI index is possible to compare people of d
  • No smoke
    no_smoking Tobacco company NO-SMOKE adorned its stand at the cigarette-type trade fair with the cigarette-shaped. The dimensions of which were 20 times the size of a regular cigarette. The regular cigarette contains 0.8 mg of nicotine. How much nicotine would a gian
  • Hollow sphere
    sphere_2 The steel hollow sphere floats on the water plunged into half its volume. Determine the outer radius of the sphere and wall thickness, if you know that the weight of the sphere is 0.5 kg and the density of steel is 7850 kg/m3
  • Tower model
    tower Tower height is 300 meters, weight 8000 tons. How high is the model of the tower weight 1 kg? (State the result in the centimeters). The model is made from exactly the same material as the original no numbers need to be rounded. The result is a three-digi

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Mass - math word problems. Power - math word problems.