The formula of heat in physics,
①Q=cm△t
②Q=I^2Rt
Characteristics of series parallel circuit (the relationship between electric power, electric heating, etc.)
such as
In series, P = P1 + P2
In parallel, P = P1 + P2
The algorithm of power can be divided into three formulas, P = UI = I * I * r = u * U / R. for a series circuit composed of several resistors in series, the current through each resistor is equal, which is determined by I * I * r. therefore, compared with other resistors, the higher the power of resistance is, the same as for a parallel circuit, the voltage of several resistors is equal, which is determined by u * U / R
Work formula of electric field force
Is w = Qu
W = Qu or w = f electric D
What are the current work formulas
w=U I T ; W= U^2 * t/R = I^2 * r *t
RELATED INFORMATIONS
- 1. In an extracurricular activity, a classmate carried out relevant observation and Research on household appliances. He took a far infrared furnace as the observation and research object Observe the far infrared furnace name plate u = 220 V P = 1 kW 220v 10(40)A Observe the name plate of electric energy meter, 50 Hz 2000 revs / kW. H Heat a pot of water with a far-infrared electric stove, turn off other household appliances, and only connect the far-infrared electric stove to the circuit to boil water, Observe the watt hour meter. The dial turns 150 revs in 5 minutes. At this time, use the thermometer (mass of water M = 2kg, initial temperature T = 30 ℃) the measured water temperature is 50 ℃ Please answer the following questions about the information obtained by this student during the activity: (1) Heat absorbed by water after heating for 5 min. (2) The electric energy consumed by the far infrared electric furnace working for 5 minutes. (3) The actual voltage of far infrared furnace. (4) The voltage of the far infrared furnace is 220 V when it works normally. Try to calculate the resistance of the wire.
- 2. Calculation of induction cooker Operation manual of induction cooker: Rated voltage: 220 V rated power: 2200 w Applicable containers: pig iron pot, stainless iron pot and enamel pot with flat bottom and 12-28cm diameter Safety note: please use the socket above 10A separately 1. Why to use more than 10A socket alone? Please explain by calculation 2. The induction cooker works normally for 30 minutes, and the consumed electric energy is______ KWh______ J.
- 3. Electric energy meter and electric power At present, I have used 3 * 10 (40) a, and now the equipment needs to be upgraded to use speed regulating motor 30kW + temperature control heating, with a total of 30kW. Can I barely use it for a period of time? If not, what may be the consequences?
- 4. Physical power calculation The mass of a car is 1.2t, the rated power is 80kW, and the car runs at 36km / h. then it accelerates and reaches the maximum speed of 180km / h after passing 700m. If the resistance in the process of driving remains unchanged, the calculation method is as follows The resistance of the road to the car Work done by the car during acceleration
- 5. Given power and time in physics, how to calculate how many kilowatts of electricity are used?
- 6. How to calculate electric power in physics? There are two formulas for calculating electric power w=uIt W = I squared RT I can't tell when to use which formula
- 7. It is proved that in a pure resistance circuit, the total power consumed on the series circuit P = UI is equal to the thermal power consumed on each resistor
- 8. In addition, after the object is put on the conveyor belt, it moves backward relative to the conveyor belt, so it is affected by the load Why is it said that when an object is put on the conveyor belt, it moves backward relative to the conveyor belt, so it moves forward due to the sliding friction given by the conveyor belt?
- 9. When the slider slides on the conveyor belt faster than the conveyor belt and can slide out of the conveyor belt, the work done by friction is equal to the product of friction and the length of the conveyor belt, so the reduction of kinetic energy of the slider is equal to the work done by friction. However, the heat generated by the system is the product of friction and the relative displacement of the slider and the conveyor belt, But at this time, the relative displacement and the length of the conveyor belt are not equal. So the formula listed according to the conservation of energy and the formula listed by the kinetic energy theorem are different. So in the conservation of energy formula, do I not list that energy? Besides the work done by friction, what is the energy conversion on the conveyor belt? What are the test points about the conveyor belt? The work done by friction and the object sliding on the conveyor belt What is the relationship between the initial velocity of the belt time? The slider is horizontal
- 10. When the voltage of 0.3V is applied, the current is 0.3A, and the motor does not rotate. When the voltage of 2.0V is applied at both ends of the motor, the current is 0.8A, and the motor works normally. What is the efficiency of the vacuum cleaner?
- 11. The calculation formula of circuit in junior high school
- 12. Find the commonly used calculation formula of junior high school science For example, the pressure calculation formula F / s represents the pressure divided by the stress area, which is very common
- 13. For junior high school all scientific calculation formula, whether it is chemical or physical, to be complete
- 14. Is the work done by the motor equal to the work done by the friction force on the conveyor belt?
- 15. The relationship between mechanical power and work and energy conversion Since work is a measure of energy conversion, the speed of doing work is also the speed of energy conversion, Why is it true that "the greater the power of a machine, the faster the machine works", Is it wrong to say that the greater the power of the machine, the faster the energy conversion when the machine is working?
- 16. The relation and difference between energy and work and force What is their unit and significance
- 17. According to what parameters of the hydraulic cylinder, what formula can be used to calculate the motor power that drives the piston movement For example, please describe the formula and process in detail,
- 18. Electric power: practical problems The resistance of a light bulb L is 10 Ω, which can normally light up under the voltage of 6V. Now connect the light bulb to 9V constant voltage power supply. In order to make the light bulb normally light up, connect a suitable resistance R in the circuit. How do you think to connect the resistance? What is the resistance value of the resistance R? The resistance of a light bulb L is 10 Ω, which can normally light up under the voltage of 6V, Now connect the bulb to 9V constant voltage power supply. In order to make the bulb shine normally, connect a suitable resistance R in the circuit. How do you think to connect the resistance? What is the resistance value of the resistance R?
- 19. Can Ohm's law and Joule's law only be used in pure resistance circuits? Why?
- 20. And knowledge points