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You are testing 100 circuit boards.  Each passes with 60% probability and the trials are independent.  Let X be the random variable for the number of circuit boards that pass.  What it the variance of X?

A  45-mH ideal inductor is connected in series with a  60-Ω resistor through an ideal 15-V DC power supply and an open switch. If the switch is closed at time t = 0 s, what is the current 7.0 ms later?

A circular coil of radius 4.5 cm and resistance 0.4 Ω is placed in a uniform magnetic field perpendicular to the plane of the coil. The magnitude of the field changes with time according to B =(1.1 t3 )T. What is the magnitude of the current induced in the coil at the time t = 2.5 s?

A conducting rod whose length is ℓ = 1.60 m is placed on frictionless U-shaped metal rails that is connected to a lightbulb having a resistance of 4.00 Ω as shown in the figure. The rails and the rod are in the plane of the page. A constant uniform magnetic field of strength 2.20 T is applied perpendicular to and out of the paper. What is the magnitude of the external applied force needed to move the rod to the right with a constant speed of 6.00 m/s?

What size capacitor should be placed in series with a 30-Ω resistor and a 40-mH inductive coil if the resonant frequency of the circuit is to be 1.0 kHz?

A theory is an idea that has been tested and refined, and is supported by experimental evidence.

The correct number of significant figures in the number “9.080 x 10-4” is

Under what clause was Roe v. Wade deemed constitutional?

Which organism would be most likely to be able to survive rapid global climate change?

The amount of CO2 in the atmosphere is stable over a period of one year.