The incandescent lamp marked with "pz22060" and the energy-saving lamp with rated power of 11W have the same brightness when they normally light up, and each lamp works normally for 10h, so the energy-saving lamp consumes less kW · h electric energy

The incandescent lamp marked with "pz22060" and the energy-saving lamp with rated power of 11W have the same brightness when they normally light up, and each lamp works normally for 10h, so the energy-saving lamp consumes less kW · h electric energy

Answer: 0.49kw · H
Analysis:
Energy consumption of incandescent lamp for 10h
W1＝Pt,P＝60W＝0.06kw
     ＝0.06kw×10h
    ＝0.6kw·h
Energy consumption of energy saving lamp:
W2＝Pt,P＝11W＝0.011kw
     ＝0.011kw×10h
    ＝0.11kw·h
Less power consumption: W1-W2 = 0.6-0.11 = 0.49kw · H

Urgent! Online. Junior physics, power related. Thank you!
Suppose that the blood delivered by the heart of a leopard is 2x10 (to the - 4th power) [the density is equal to that of water treatment], and the average value of its blood pressure (which can be regarded as the pressure of blood delivery) is 3x10 (to the 4th power) Pa. suppose that the heart beat of a leopard is about 75 times per minute, what is the average power of the heart?
Find the process

Assuming that the cross-sectional area of the blood vessel is s (m ^ 2), the distance equivalent to pushing blood each time is L = 2x10 ^ - 4 (m ^ 3) / S (m ^ 2)
Then the pressure is f = P * s
One time work of heart beat W1 = f * l = P * s * l = (3 * 10 ^ 4 PA) * s (m ^ 2) * (2x10 ^ 4 (m ^ 3) / S (m ^ 2))
=6 J
One minute work w = 75 * 6J = 450j
Power P = w / T = 450W / 60s = 7.5W

When you cooperate with your classmates to measure the power of people going upstairs, what are the measuring tools you need______ The physical quantities to be measured are______ Power expression p=______ ．

The answer is: platform scale, tape measure, stopwatch; mass m, height h, climbing time t; P = mght

The known set a = {x | x ^ 2 + 4x = 0}, B = {x | x ^ 2 + 2 (a + 1) x + A ^ 2-1 = 0}
If a ∪ B = B, find the value range of real number a

Because x ^ 2 + 4x = 0
So x = 0 or x = - 4
Set a is {0, - 4}
If a ∪ B = B, because a = {0, - 4}
So a ∪ B must contain 0 and - 4 elements, and B has at most two elements
So B = {0, - 4}
If B = {0, - 4}
So 4 (a + 1) ^ 2-4a ^ 2 + 4 > 0
a>-1
Substitute x = 0 and x = - 4 into the equation respectively
We get a ^ 2-1 = 0 and 16-8 (a + 1) + A ^ 2-1 = 0
From a ^ 2-1 = 0, we can get a = 1 or a = - 1
From 16-8 (a + 1) + A ^ 2-1 = 0
We get a ^ 2-8a + 7 = 0
A = 1 or a = 7
If the solution is 0 and - 4, only a = 1
We get a = 1

Why can electric energy conversion in refrigerator work
Professional detailed 300 words below do not disturb, I will add points

1) Compression refrigerator: this kind of refrigerator is provided with mechanical energy by the motor, and works on the refrigeration system through the compressor. The refrigeration system is made of the principle that the refrigerant with low boiling point absorbs the heat of vaporization when evaporating. It has the advantages of long service life, convenient use and easy operation, At present, 91-95% of the refrigerators in the world belong to this category, 2) absorption refrigerator: this kind of refrigerator can use heat source (such as gas, kerosene, electricity, etc.) as power. The purpose of refrigeration can be achieved by using ammonia water hydrogen mixed solution in the continuous absorption diffusion process, 3) semiconductor refrigerator: it uses PN type semiconductor to supply direct current, The principle of Peltier effect on the node is used to realize refrigeration. 4) chemical refrigerator is a refrigerator that uses some chemical substances dissolved in water to absorb heat strongly to obtain refrigeration effect. 5) electromagnetic vibration refrigerator is a refrigerator that uses electromagnetic vibrator as the driving force to drive the compressor. Its principle and structure are basically the same as those of compression refrigerator 6) Solar refrigerator: it uses solar energy as refrigeration energy. 7) insulation demagnetization refrigeration refrigerator. 8) radiation refrigeration refrigerator. 9) solid refrigeration refrigerator

X of a * (x + 2) and y of B * (x + 2)

x/a(x+2)=bx/ab(x+2)
y/b(x+2)=ay/ab(x+2)

The rated voltage of a festival lantern is 12V, which should be connected to the household circuit of 220V
I would like to ask: at least how many such small lights in series use?
If in use, the current through the first small color lamp is 200mA, how much is the current through the tenth small color lamp?

According to the voltage formula of series circuit, u = U1 + U2 +. + UN
We get 12x = 220. We get x = 18.33333
Because it can't be higher than the rated voltage, 19 are needed
The current of the series circuit is equal, and the current through the 10th small color lamp is also 200mA

The calculation result of (x ^ 2 + MX) (x ^ 2-nx + 1) does not contain the items of x ^ 2 and x ^ 3, and the values of M and N are calculated
emergency

(x^2+mx)(x^2-nx+1)=x^4-nx^3+x^2+mx^3-mnx^2+mx=x^4+(m-n)x^3+(1-mn)x^2+mx
There are two groups of solutions, M = n = 1, M = n = - 1

The watt hour meter is 220V 5 (10) a, 3000r / kWh, the watt hour meter turns 60R in 1min, what is the total power of household appliances? It does not exceed the index,
The home circuit can also add several 40W lamps

W = 60 / 3000 * 1kwh = 1 / 50kwh; t = 60s = 0.1h; so p = w / T = (1 / 50) / 0.1h = 2kW; so the total power of the electric energy meter of 220v10a is 220V * 10A = 2.2kW; remove 2kW current power, so there is 0.2KW left, that is 200W, so 200W / 40W = 5;

If the root number of the simplest quadratic radical (xsquare-7) and the root number (8x + 2) are the same, then the value of X is?

For example, there is X & # 178; - 7 = 8x + 2
x²-8x-9=0
(x-9)*(x+1)=0
So x = 9 or x = - 1