Energy - practice problems - page 6 of 10
Number of problems found: 181
- 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? - Strawberries 16473
On the farm, twelve part-timers planned to harvest a crop of strawberries in 5 days. On the fifth day in the weather forecast, they reported rain. How many part-timers will they need to harvest the strawberries in four days? - A hammer
A hammer weighing 500 g hits the nail at a speed of 3 m/s. What is the average force acting on the nail, which penetrates the board to a depth of 5 cm?
- Weighing 12481
A stone weighing 200g falls in a free fall for 3 s. Find its kinetic energy on impact. - Weighing 12471
Compare the kinetic energy of a man weighing 80 kg who runs at a speed of 2 m/s and missiles weighing 20 g fired at 400 m/s. - Determine 12461
The 150t aircraft takes off at a speed of 288km/h and, after a while, reaches a speed of 900km/h. Determine the change in the kinetic energy of the aircraft. - Increased 12441 A car traveling at a speed of 25km/h increased the speed to a) 75km/h b) 100km/h when exiting the highway. How many times has its kinetic energy increased?
- Potential 12431 From what height does a hammer weighing 200 kg fall if its initial potential gravity was 6 kJ?
- The elevator
The elevator car weighing 400 kg rises from the third to the fifth floor. By what value will the potential gravitational energy of the cabin increase? What useful work will the elevator motor do? The height of one floor is 5m. - Gravitational 12411 We lift a weight of 2 kg to a height of 50 cm above the top of the table. Determine its gravitational potential energy: a) relative to the tabletop, b) relative to the floor if the table top is 1m above the floor.
- Positional 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 of 50 m?
- Horizontally 11211
A boy weighing 50 kg moves horizontally by 10 m. What is his kinetic energy at a speed of 1 m/s? - Horizontally 11201 A boy weighing 50 kg moves horizontally by 10 m. How much has his positioning energy increased?
- 3 phase load
Two wattmeters are connected to measure 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) the second reading is negative. - Kilowatt-hours
If the Lewis family used 648 kilowatt-hours of electricity in 12 days at the same usage rate, how many kilowatt-hours should they use in 24 days? - Friction coefficient
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 - Calories 2
Ben eats approximately 2400 calories per day. His wife Sarah eats 5/8 as much. How many calories does Sarah eat per day? - Power input
The construction lift lifted a 300 kg load to a height of 12 m with uniform movement. If the efficiency is 75% and the engine has a power input of 5 kW, how long did it take for the load to be lifted?
Twelve workers would earn € 800 in 10 days. How many euros would 14 workers earn in 8 days?Do you have homework that you need help solving? Ask a question, and we will try to solve it. Solving math problems.
