Two coils are mutually coupled, with L1=50 mH, L2=120 mH, and k=0.5. Calculate the maximum possible equivalent inductance if the coils are connected in parallel

Calculate the inductance, $L$, for the following long coils: (Note: $1\text{ m}=100\text{ cm}$ and $1\text{ m}^2=10,000\text{ cm}^2$.) a. air core, $20$ turns, area $3.14\text{ cm}^2$, length $25\text{ cm}$. b. same coil as step a with ferrite core having a $\mu_\text{r}$ of $5000$. c. air core, $200$ turns, area $3.14\text{ cm}^2$, length $25\text{ cm}$. d. air core, $20$ turns, area $3.14\text{ cm}^2$, length $50\text{ cm}$. e. iron core with $\mu_\text{r}$ of $2000$, $100$ turns, area $5\text{ cm}^2$, length $10\text{ cm}$.

In a tensile test, the starting gage length $=100.0 \mathrm{~mm}$ and the cross-sectional area $=150 \mathrm{~mm}^2$. During testing, the following force and gage length data are collected: (1) $17,790 \mathrm{~N}$ at $100.2 \mathrm{~mm}$, (2) $23,040 \mathrm{~N}$ at $103.5 \mathrm{mm}$, (3) $27,370 \mathrm{~N}$ at $110.5 \mathrm{~mm}$, (4) $28,910 \mathrm{~N}$ at $122.0 \mathrm{~mm}$, (5) $27,480 \mathrm{~N}$ at $130.0 \mathrm{~mm}$, and (6) $20,460 \mathrm{~N}$ at $135.1 \mathrm{~mm}$. The final data point (6) occurred immediately prior to failure. Yielding occurred at a load of $19,390 \mathrm{~N}$, and the maximum load (4) was $28,960 \mathrm{~N}$. (a) Plot the engineering stress strain curve. Determine (b) yield strength, (c) modulus of elasticity, (d) tensile strength, and (e) percent elongation.

Determine the total inductance of each circuit in Figure earlier

Define tensile strength of a material.

How many turns are required to produce $30 \mathrm{mH}$ with a coil wound on a cylindrical core having a cross-sectional area of $10 \times 10^{-5} \mathrm{~m}^2$ and a length of $0.05 \mathrm{~m}$ ? The core has a permeability of $1.2 \times 10^{-6} \mathrm{H} / \mathrm{m}$

What is Hooke's law?

If the bleeder current, $I_\text{B}$, is $15\text{ mA}$ in Fig. 7–32, solve for a. $I_1$, $I_2$, $I_3$, and $I_\text{T}$. b. $V_1$, $V_2$, and $V_3$. c. $R_1$, $R_2$, and $R_3$. d. The power dissipated by $R_1$, $R_2$, and $R_3$.

Use MATLAB to plot the following sinusoid for $0<t<5$

$$8 \sin (\pi t+\pi / 4)+10 \cos (\pi t-\pi / 8)$$

The primary of an ideal transformer with a turns ratio of 5 is connected to a voltage source with Thevenin parameters

$$v_{Th} = 10 cos 2000t V$$

and

$$R_{Th} = 100 Ω.$$

Determine the average power delivered to a 200-Ω load connected across the secondary winding.

A transformer is used in stepping down or stepping up: (a) dc voltages (b) ac voltages (c) both dc and ac voltages

A 1,200/240-V rms transformer has impedance 60∠-30°Ω on the high-voltage side. If the transformer is connected to a 0.8∠10°-Ω load on the low-voltage side, determine the primary and secondary currents when the transformer is connected to 1200 V rms.

Design a problem to help other students better understand ideal transformers.

A 480/2,400-V rms step-up ideal transformer delivers 50 kW to a resistive load. Calculate the secondary current.