Energy - practice problems - page 5 of 9
Number of problems found: 177
- Stroller 36521
Mom did a 5kJ job pushing the stroller. She always pushed him on the plane with a force of 50N. How far did she push the stroller? - Weighing 36511
The crane lifted a concrete block weighing 3 tons to a height of 500 cm. What work did it do? - Constant 36313
The truck weighs 4.5 tons and is moving at a constant speed of 72 km/h. How big is his kinetic energy? - Electric cooker
During which time, 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
- Harmonic oscillator
Calculate the total energy of a body performing a harmonic oscillating motion if its mass is 200 g, the deflection amplitude is 2 cm, and the frequency is 5 Hz. Please round the result to 3 decimal places. - Concrete column
The concrete column of the highway bridge has the shape of a block with dimensions of 1m x 0.8m x 25m. Crane should lift it to a height of 20m. What is the power of his engine if the lifting takes 2 minutes? - 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) - 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. - Inclined plane
1. How much work W do we have to do to pull a body weighing 200 kg along an inclined plane with a length of 4 m to a total height of 1.5 m? 2. Find the force we need to exert to do this if we neglect frictional resistance. 3. Find the force we would need
- Water mixing
We have 520 ml of hot water and 640 ml of water at 48°C. What is the temperature of approximately hot water when the resulting mixture has a temperature of 65°C? - 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. - Resistance 25021
Calculate the resistance and power of the appliance through which a current of 20mA flows at the mains voltage (230 V). - The coal
The coal stock would be enough to heat a larger room for 12 weeks and a smaller one for 18 weeks. It was heated for four weeks in both rooms, then only in a smaller one. How long was the coal stock enough? - Energy consumption
The device is connected to 230V and draws a 3.5A current. Power consumption is 1932kJ. How many minutes has this device been in operation?
- Movement 21953
We lift a box weighing 50 kg onto a railway wagon with a precise movement along a 3m track. We will use a fixed pulley. What is the pulling force on the free end of the rope? - Cooker
A current of 2A passes through the immersion cooker at a voltage of 230V. What work do the electric field forces do in 2 minutes? - Transformer 20073
The transformer is oil-cooled and transforms a power of 20MW with an efficiency of 92%. Determine the temperature of the oil at the outlet of the transformer if the oil was 20°C when it entered the transformer. 2.5 liters of oil will flow through the tran - Surroundings 19153
A heating element with a resistance of 1.6 Ω is used to heat the car's rear glass. The body is connected to the battery in the car, which has a voltage of 12 V. a) What is the power input of the heating element? b) How much heat does the heating element g - Temperature 16633
What heat do we need to supply a copper body weighing 8 kg to raise its temperature by 136 degrees Celsius?
Do you have homework that you need help solving? Ask a question, and we will try to solve it.