First question (upper left): 1/Req = 1/12 + 1/24 = 1/8 Req = 8 ohms Voltage is equal through different resistors, and V1 = V2 = 24 V. Current varies through parallel resistors: I1 = V1/R1 = 24/12 = 2 A. I2 = 24/24 = 1 A.
Second question (middle left): V1 = V2 = 6 V (parallel circuits) I1 = 2 A, I2 = 1 A, IT = 2+1 = 3 A. R1 = V1/I1 = 6/2 = 3 ohms, R2 = 6/1 = 6 ohms, 1/Req = 1/2 + 1/1, Req = 2/3 ohms
Third question (bottom left): V1 = V2 = 12 V IT = 3 A, meaning Req = V/It = 12 V/3 A = 4 ohms 1/Req = 1/R1 + 1/R2, 1/4 = 1/12 + 1/R2, R2 = 6 ohms I1 = V/R1 = 1 A, I2 = V/R2 = 2 A
Fourth question (top right): 1/Req = 1/20 + 1/20, Req = 10 ohms IT = 4 A, so VT = IT(Req) = 4*10 = 40 V Parallel circuits, so V1 = V2 = VT = 40 V Since the resistors are identical, the current is split evenly between both: I1 = I2 = IT/2 = 2 A.
Fifth question (middle right): 1/Req = 1/5 + 1/20 + 1/4, Req = 2 ohms IT = VT/Req = 40 V/2 ohms = 20 A V1 = V2 = V3 = 40 V The current of 20 A will be divided proportionally according to the resistances of 5, 20, and 4, the factors will be 5/(5+20+4), 20/(5+20+4), and 4/(5+20+4), which are 5/29, 20/29, and 4/29. I1 = 20(5/29) = 100/29 A I2 = 20(20/29) = 400/29 A I3 = 20(4/29) = 80/29 A
Sixth question (bottom right): V2 = 30V is given, but since these are parallel circuits, V1 = VT = 30 V. Then I1 = V1/R1 = 30 V/10 ohms = 3 A. I2 = 30 V/15 ohms = 2 A. IT = 3 + 2 = 5 A 1/Req = 1/10 + 1/15, Req = 6 ohms
Simple machines are useful because they reduce effort or extend the ability of people to perform tasks beyond their normal capabilities. Simple machines that are widely used include the wheel and axle, pulley, inclined plane, screw, wedge and lever.
C) During chemical reaction, total mass remains the same.
This is because due to the law of conservation of mass, stating that in a chemical reaction, neither mass will be created nor destroyed. So, the total mass will not change when chemical reactions occur.
The speed of electromagnetic waves in a vacuum is the same as the speed of light. It can be measured by finding the frequency and wavelength of two different waves, and then by that correlation, the speed of the waveform. Hope this helps you (: