# Power - math word problems

Power is the amount of work done (energy supplied) per unit time. In physics, power is the amount of energy transferred or converted per unit time. In the SI units, the unit of power is the watt, equal to one joule per second. Other units are, for example, 1 hp (one horsepower; 1 hp = 735.5 W) and then derived units such as kW - kilowatt.

#### Number of problems found: 256

• 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
• Gain Find the gain whenever the output power is 21x the input power. 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
• Simplest form Find the simplest form of the following expression: 3 to the 2nd power - 1/4 to the 2nd power
• Decibel A circuit has an input power of 58 mW. Its output power is 6 mW. What is the loss in decibels?
• Motor physics Car traveling at 130 km/h on the highway. Pulling power of the motor is 8 kN. Determine engine power in kW.
• One third power Which equation justifies why ten to the one-third power equals the cube root of ten?
• Bulbs In the box are 6 bulbs with power 75 W, 14 bulbs with power 40 W and 15 with 60 W. Calculate probability that a randomly selected bulb is:
• Powers 3 2 to the power of n divided by 4 to the power of -3 equal 4. What is the vaule of n?
• Electric input power 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 =?
• Power line pole From point A, the power line pole is seen at an angle of 18 degrees. From point B to which we get when going from point A 30m away from the column at an angle of 10 degrees. Find the height of the power pole.
• Efficiency What is the power output of kettle 2 kW with efficiency 90%?
• Density 2 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?
• Pump What power has a pump output to move 4853 hl of water to a height of 31 m for 8 hours?
• Unknown number 7 Calculate unknown number whose 12th power when divided by the 9th power get a number 27 times greater than the unknown number. Determine the unknown number.
• Granddaughter In 2014, the sum of the ages of Meghan's aunt, her daughter and her granddaughter was equal to 100 years. In what year was the granddaughter born, if we know that the age of each can be expressed as the power of two?
• Electric work Calculate the work done by the electric forces passing the current of 0.2 A through the bulb in 10 minutes if the bulb is connected to a 230 V power supply.
• Motorcycle engine The motorcycle engine has a constant power of 1.2 kW for 0.5 hours. How much work does the engine do? Express work in kWh and Ws units.
• 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 coun
• Derivative problem The sum of two numbers is 12. Find these numbers if: a) The sum of their third powers is minimal. b) The product of one with the cube of the other is maximal. c) Both are positive and the product of one with the other power of the other is maximal.

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