The phasor technique is not valid if the frequencies of the sinusoids in the time domain are different. Part F - Use phasors to combine sinusoids The phasor technique makes it pretty easy to combine several sinusoidal functions into a single sinusoidal expression without using trigonometric identities. However, you cannot use the phasor technique in all cases. Select the expressions below for which the phasor technique cannot be used to combine the sinusoids into a single expression.
a. 45 sin(2500t – 50°) + 20 cos(1500t +20°)
b. 25 cos(50t + 160°) + 15 cos(50t +70°)
c. 100 cos(500t +40°) + 50 sin(500t – 120°) – 120 cos(500t + 60°) -100 sin(10,000t +90°) + 40 sin(10, 100t – 80°) + 80 cos(10,000t)
d. 75 cos(8t+40°) + 75 sin(8t+10°) – 75 cos(8t + 160°)

Answer:

  a, c

Explanation:

As the problem statement tells you, the phasor technique cannot be used when the frequencies are different. The frequencies are different when the coefficients of t are different. The different ones are highlighted.

a. 45 sin(2500t – 50°) + 20 cos(1500t +20°)

b. 25 cos(50t + 160°) + 15 cos(50t +70°)

c. 100 cos(500t +40°) + 50 sin(500t – 120°) – 120 cos(500t + 60°) -100 sin(10,000t +90°) + 40 sin(10, 100t – 80°) + 80 cos(10,000t)

d. 75 cos(8t+40°) + 75 sin(8t+10°) – 75 cos(8t + 160°)

Answer:

Based on the concept that it is better to prevent falls happening in the first place, which of the following safety methods meets that criteria?

Iman wanted to find out at what temperature butter melts. She placed a cube of solid butter in a beaker. She put the beaker on a hot plate. She turned up the temperature dial one degree every two minutes. Then she recorded the temperature at which the butter started to melt.

Iman wanted to determine if her results were reliable. She decided to repeat the experiment. Which statement describes the main purpose of repeating the experiment?


to test a different substance

to see if the results are similar

to practice completing experiments

to determine if butter will melt twice

Una cuerda fuertemente estirada tiene sus puntos extremos fijos en x=0 y x=L. Si se le da un desplazamiento inicial F(x)=ax(L-x) desde la posición de equilibrio. Donde a es una constante y luego se suelta, encuentre el desplazamiento en cualquier tiempo t>0. Donde c=1/π.

Switching to first order kinetics, enzymes are immobilized in 6 mm radius (R) beads. Beads are immersed in a solution containing substrate at a concentration (CAs) of 22 gmol/m3. The observed reaction rate (rA,obs) of the heterogeneous reaction is 4.3 x 10-6 gmol/sec. The first order rate constant (k1) is 0.24 /sec. Calculate the hypothetical rate, r*As of the reaction in this system.