Answer:
a)
b)
Explanation:
The current flowing in a R-L series circuit is given by
Where τ is the time constant and is given by
Where L is the inductance and R is the resistance
Assuming the current has reached steady state when it is at 99% of its maximum value,
Therefore, it would take t = 4.6τ to reach the steady state.
(b) If an emergency power circuit needs to reach steady state within 1.2 ms of turning on and the circuit has a total resistance of 72 Ω, what values of the total inductance of the circuit are needed to satisfy the requirement?
Therefore, an inductance of 0.0187 H is needed to satisfy the requirement.
Effort force and Resistance force
Answer:
E = 10t^2e^-10t Joules
Explanation:
Given that the current through a 0.2-H inductor is i(t) = 10te–5t A.
The energy E stored in the inductor can be expressed as
E = 1/2Ll^2
Substitutes the inductor L and the current I into the formula
E = 1/2 × 0.2 × ( 10te^-5t )^2
E = 0.1 × 100t^2e^-10t
E = 10t^2e^-10t Joules
Therefore, the energy stored in the inductor is 10t^2e^-10t Joules
Answer:
He should use 90 for Q3 ⇒ answer A
Explanation:
Lets explain the meaning of Q3
Q1 is the "middle" value in the first half of the data set
Q2 is the median value in the set
Q3 is the "middle" value in the second half of the data set
The data are
76 , 79 , 81 , 83 , 85 , 86 , 89 , 91 , 93
The set has nine numbers, then Q2 is the fifth one
Q2 = 85
The first half of the data are:
76 , 79 , 81 , 83
The second half of the data are:
86 , 89 , 91 , 93
They are four numbers, then the middle one is the average of the
second and the third numbers
Q3 =
<em>He should use 90 for Q3 </em>