If a motor is marked with "220V & nbsp; 10A" and the coil resistance is 3 Ω, the electric power is 0______ W. The thermal power is______ W. The efficiency is______ .

If a motor is marked with "220V & nbsp; 10A" and the coil resistance is 3 Ω, the electric power is 0______ W. The thermal power is______ W. The efficiency is______ .

The results show that when the thermal power is 2 200 W × 2 200 W, the total thermal power is 2 200 W × 1 900 W, so the thermal power is 2 200 W × 1 900 W, and the total thermal power is 2 200 W × 1 900 W
In the triangle ABC, ab = AC = m, the bottom edge is a, the height of the bottom edge is h, the perimeter is l, and the area is s
The relationship between variable s and variable h when a is constant
The relationship between variable a and variable h when s is constant
∵S=1/2ah
When a is constant, s is a positive proportional function of A
∵a=2S/h
When s is constant, a is the inverse proportional function of H
S = a × h. When a is fixed, the higher the S is, the larger the H is. When s is fixed, the larger the power function a is, the smaller the H is
In the arithmetic sequence {an}, the tolerance d > 0. If the sum of the first n terms is Sn and satisfies a2a3 = 45. A1 + A4 = 14, find the general term formula of the sequence {an}
a2=a1+d a3=a1+2d a4=a1+3d
a2a3=(a1+d)(a1+2d)=45
a1+a4=a1+a1+3d=14
a1=1
D=4
an=a1+4(n-1)
a2=5,a3=9
an=4n-3
Through the electric furnace wire, the coil current of the motor is I, and their resistance is R. who has the most electric power?
The electric furnace wire can be regarded as a pure heating appliance, which outputs heat
But the motor is mainly external output power, extra heat
The power formula of electric heating is I ^ 2R, but the motor will output extra power, so when the current and resistance are the same, the power of the motor is larger
It must be the motor, the current and resistance are the same, which means that the heat generated by the two is the same, but the motor has to do external work, so the motor power is large. Because the explanation you gave is not detailed, there are also special cases, when the motor stalls, it does not do external work, then the two powers are the same. And when the motor is idling, if we ignore all kinds of friction loss, we can think that the power of the two is the same. ... unfold
It must be the motor, the current and resistance are the same, which means that the heat generated by the two is the same, but the motor has to do external work, so the motor power is large. Because the explanation you gave is not detailed, there are also special cases, when the motor stalls, it does not do external work, then the two powers are the same. And when the motor is idling, if we ignore all kinds of friction loss, we can think that the power of the two is the same. Put it away
Same current, same resistance, same power!
Is the area of a triangle a function of its perimeter? Is there a functional relationship between them
Explain why
If you want to draw an equilateral triangle and a right triangle (3,4,5) with a circumference of 12, they have the same perimeter and different areas, so the area of the triangle depends on the shape, so there is no fixed functional relationship between the perimeter and the area;
no
It is known that the sequence {an} is an arithmetic sequence, the sum of the first n terms is Sn, the tolerance d > 0, and a2a3 = 28, a1 + A4 = 11
It is known that the sequence {an} is an arithmetic sequence, the sum of the first n terms is Sn, the tolerance d > 0, and a2a3 = 28, a1 + A4 = 11. Find the general term formula of the sequence {an}
a2+a3=a1+a4=11
a2a3=28
Because d > 0
So A2 = 4, A3 = 7
So d = 3
a1=1
an=1+3(n-1)
According to the meaning of the title:
a2*a3=28
a1+a4=a2+a3=11
And tolerance d > 0, so A3 > A2
The solution is A2 = 4, A3 = 7
So d = a3-a2 = 3, A1 = a2-d = 1
So an = 1 + 3 (n-1) = 3n-2 (n ≥ 1)
A2a3 = (a1 + D) (a1 + 2D) = 28, a1 + A4 = 2A1 + 3D = 11, substituting: (11 + D) (11-d) / 4 = 28, D & sup2; = 9, d = 3, A1 = 1;
an=1+3（n-1)=3n-2
a1+a4=11=a2+a3
a2a3=28
D>0
a2=4
a3=7
D=3
a1=1
an=1+3(n-1)
a2=a1+d,a3=a1+2d,a1=a1,a4=a1+3d
Because A2 * A3 = 28
a1+a4=11
So, a1 + 28 (d) = 2
a1+(a1+3d)=11
The solution is A1 = 1
D=3
So an = 1 + (n-1) * 3 = 3n-2
According to the meaning of the title, A2 + a3 = 11 {A2 + a3 = 11, a2a3 = 28
The solution is {A2 = 4, A3 = 7 {A2 = a1 + D, A3 = a1 + D, that is {4 = a1 + D, 7 = a1 + 2D
The solution is {d = 3, A1 = 1
So an = 1 + (n-1) * 3
(formula application: an = a1 + (n-1) d;
In the arithmetic sequence, if n + M = x + y, then an + am = ax + by;)
For a DC motor, the rated voltage is 24 V, the electric power is 120 W, and the resistance of the internal coil is 0.5 Ω. If the motor works normally for 5 minutes, find out: (1) how much J work is done by the current; (2) how much J heat is produced; (3) how much J electric energy is converted into mechanical energy
Current work w = Pt = 120W × 300s = 3.6 × 104j current I = Pu = 120w24v = 5A heat generated q = i2rt = (5a) 2 × 0.5 Ω × 300s = 3750j mechanical energy w ′ = w-q = 3.6 × 104j-3750j = 32250j. Answer: current work is 3.6 × 104j, heat generated is 3750j, mechanical energy converted is 32250j
If the sum of the lengths of the two right angle sides of the coordinate triangle of the function y = - 3 / 4x + B (B is a constant) is 14, the area of the triangle can be obtained?
The intersection points of the line and the coordinate axis are (0, b), (4 / 3b, 0), and | B + 4 / 3b | = 14, so | B | = 6, so the area of the triangle s = 1 / 2 * | B | * | 4 / 3b | = 24
x=0,y=b
y=0,x=4/3b,
That is, B + 4 / 3B = 14, B = 6,
The area is 1 / 2bx4 / 3B = 24,
Just draw a picture for yourself.
Thank you. Hope to get the best answer
3 / 4 is the slope, 14 / (3 + 4) = 2,
2 * 3 = 6, 2 * 4 = 8, don't worry about that side and that side, you only know the value of two straight lines. The minus sign just determines the position of the triangle, not the size. B is either 6 or 8. It doesn't matter. There's no need to confirm the value of B.
tan=sin/cos
3 corresponds to y
4 corresponds to X
3+4=7
So zoom in twice
It is 6 and 8, and the area is 6 * 8 / 2 = 24
How is the sum formula Sn = Na1 + n (n-1) / 2 * D derived from the first n terms of arithmetic sequence?
Sn = a1 + A2 +. An-1 + an
Sn=an+an-1+.a2+a1
By adding the two formulas, 2Sn = (a1 + an) + (A2 + an-1) + (an + A1)
N
=n(a1+an)
So SN=
The resistance of a motor coil is 2 Ω, the voltage of the motor in normal operation is 220 V, and the current is 10A. (1) how much work does the current do when the motor works continuously for 10 minutes? How much electric energy is converted into internal energy? (2) If the motor is stuck for too long, it will burn the coil. Why?
(1) The motor works continuously for 10 minutes, the work done by current: w = uit = 220 V × 10 a × 10 × 60 s = 1.32 × 106 J, the internal energy converted from electric energy: q = i2rt = (10a) 2 × 2 Ω × 10 × 60 s = 1.2 × 105 J; (2) if the motor is stuck, because the motor is connected to the circuit of coil, the coil resistance