Energy + fundamentals of Physics - practice problems - last page
Number of problems found: 117
- Bulb
A 60 W bulb consumes 0.12 kWh of electricity. How long did she stand light without a break? - The appliance
The appliance has a power input of 2.3 kW. It is connected to the mains voltage of 230 V. What is the current flowing through the appliance? - Filament of bulb
The bulb's filament has a 1-ohm resistivity and is connected to a voltage of 220 V. How much electric charge will pass through the fiber when the electric current passes for 10 seconds? - A steel
A steel hammer with a weight of 0.5 kg hits the nail at a speed of 3 m/s. How deep the nail penetrates the wood if the hammer acts on the nail with an average force of 50N.
- Calculate: 5656
Janko is skating at a speed of 18 km/h. Its kinetic energy is 0.5 kJ. Janko weighs 40 kg. Calculate: 1. what work will the braking forces do before Janko stops? 2. How big is the braking force when Janko stops after crossing a track of 14 m.? - Granddaughter 4237
Mrs. Helena has an old cell phone with nothing to do but makes phone calls. The cell phone will discharge in 72 hours when fully charged and on the phone. Three hours of calling in a row are enough to discharge a fully charged phone. After the last full c - Efficiency 4073
Determine the efficiency of a vacuum cleaner with a power input of 1.2 kW when the suction power is 360 W. - Efficiency 4072
What kind of work did the mixer with an efficiency of 30% do when it did 4.5 kWh of work? - Efficiency
What is the power output of a kettle 2 kW with an efficiency of 90%?
- Vertically 3237
The body weighing 100g is ejected from the surface of the Earth vertically upwards at an initial speed of 30m. s-1. Determine the height at which the body rises and its potential energy at the path's highest point. - Water temperatures
To 25 liters of water at 50 °C, we add 15 liters of water at a different temperature. How many °C should the water be colder than 50 °C so that 40 liters of the water obtained has a temperature of 42.5 °C? - Locomotive
Locomotive pulled a permanent train load of 200 kN horizontally along the track of 5km. What work has it done? - Elevator
In homes with more floors, 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 co - Shot
Shot with a mass 43 g flying at 256 m/s penetrates into the wood to a depth 25 cm. What is the average force of resistance of wood?
- Car
At what horizontal distance reaches the car weight m = 753 kg speed v = 74 km/h when the car engine develops a tensile force F = 3061 N. (Neglect resistance of the environment.) - Motor physics
A car is traveling at 98 km/h on the highway. The pulling power of the motor is 6 kN. Find the engine power in kW. - Decibel
A circuit has an input power of 92 mW. Its output power is 12 mW. What is the loss in decibels?
Do you have homework that you need help solving? Ask a question, and we will try to solve it.