A DC current does not go through the capacitor after the initial charging. Check the equation that describes the impedance in RC circuits when the frequency f decreases to zero (which is the case of any DC current). Explain qualitatively why an AC current can go through a capacitor , but a DC current cannot.
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A parallel plate capacitor with plate separation d is connected to a battery. The capacitor is fully charged to Q Coulombs and a voltage of V volts. Let C be the capacitance and U the stored energy. Select True or False for each statement.
1. After being disconnected from the battery, decreasing d increases C.
2. With the capacitor connected to the battery, decreasing
d increases C.
3. With the capacitor connected to the battery, decreasing
d decreases Q.
4. With the capacitor connected to the battery, inserting a
dielectric with κ > 1 will decrease Q.
5. With the capacitor connected to the battery, decreasing
d increases U.
6. With the capacitor connected to the battery, inserting a
dielectric with κ > 1 will decrease U.
Please explain thoroughly! Will Rate!
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A 0.836 kg toy car is powered by one 9V battery (9.00 V) connected directly to a small DC motor. The car has an effective energy conversion efficiency of 36.1 % , meaning that 36.1 % of the electric energy applied to the motor is converted into translational kinetic energy. After 7.88 s , the car, which is initially at rest, reaches a speed of 3.43 m / s . What is the average current supplied to the car's motor?
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A portable radio is sitting at the edge of a balcony 5.1 m above the ground. The unit is emitting sound uniformly in all directions. By accident, it falls from rest off the balcony and continues to play on the way down. A gardener is working in a flower bed directly below the falling unit. From the instant the unit begins to fall, how much time is required for the sound intensity level heard by the gardener to increase by 10.0 dB?
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A transformer is intended to decrease the value of the alternating voltage from 500 volts to 25 volts. The primary coil contains 200 turns. Find the necessary number of turns N2 in the secondary coil.
A transformer is intended to decrease the value of the alternating current from 500 amperes to 25 amperes. The primary coil contains 200 turns. Find the necessary number of turns N2 in the secondary coil.
In a transformer, the primary coil contains 400 turns, and the secondary coil contains 80 turns. If the primary current is 2.5 amperes, what is the secondary current I2?
A transformer supplies 60 watts of power to a device that is rated at 20 volts. The primary coil is connected to a 120-volt ac source. What is the current I1 in the primary coil?
The voltage and the current in the primary coil of a nonideal transformer are 120 volts and 2.0 amperes. The voltage and the current in the secondary coil are 19.4 volts and 11.8 amperes. What is the efficiency e of the transformer? The efficiency of a transformer is defined as the ratio of the output power to the input power, expressed as a percentage: e=100Pout/Pin.
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A copper wire has a diameter of 3.247 mm. What magnitude of current flows when the drift velocity is 4.40 mm/s? Take the density of copper to be 8.92 g/cm3. Give your answer in Amperes.
PLEASE PLEASE PLEASE answer correctly
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Givens:
Altitude: FL310 (31,000 ft Pressure Altitude)
Indicated Airspeed: 250 KIAS
Indicated Outside Air Temperature (IOAT) or Total Temperature: -30 deg C
Figure 2.1 for Atmosphere
Figure 3.1 Position Errors
Figure 3.2 Compressibility Errors
Figure 11.2 or Tt = Ta (1 + .2M2) Temperature Ram Rise
1. Find CAS (Calibrated Airspeed in kts).
2. Find EAS (Equivalent Airspeed in kts).
3. Find Pressure Ratio: .
4. Find Mach.
5. Find Actual Outside Air Temperature (ambient temperature).
6. Find Temperature Ram Rise.
7. Find Density Ratio: .
8. Find TAS, True Airspeed in kts.
9. If you are landing into an airfield in mountainous terrain at a field elevation of 3,000 ft
MSL (Mean Sea Level) and the field outside air temperature is -24 deg C, according to
AC 91-XX Draft Appendix 2, how should you adjust your approach arrival procedures
with a Final Approach Fix (FAF) at 5,000 ft MSL and your Minimum Descent Altitude
(MDA) at 3500 ft MSL?
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Four point masses are arranged as follows: m1 = 5.76 g at (0,19.6 cm), m2 = 2.25 g at (19.6, 0) cm, m3 = m1 at (0,-19.6) cm and m4 = m2/.49 at (-19.6, 0) cm. These are all immovable
a) In unit vector notation, what is the net gravitational force from them on a point with mass m5 = 2.56 g at the origin?
b) If m5 was free to move and released from rest what will its speed be after travelling 9.8 cm?
c) Imagine a new configuration where m2 has been removed. What would then be the new answer to part b?
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An insulated wall consists of an exterior wood layer of thickness 3.1 cm and an interior layer of foam insulation of thickness 2.3 cm . For the wood, k=0.080W/(m⋅K), and for the foam insulation k= 0.010 W/(m⋅K). The outer surface of the wood is at a constant -15.0 ∘C , and the inner surface of the foam insulation is at a constant 19.0 ∘C .
Calculate the temperature in Celsius where the wood and foam insulation are in contact. T=???
Calculate the heat flow per unit area through the two-layer wall. H=?? W/m^2
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When t = 0, the position of a point is s= 6m, and its velocity is v= 2m/s. From t = 0 to t= 6s, the acceleration of the point is a = 2+ 2t2 m/s2 .From t = 6s until it comes to rest, its acceleration is a = -4m/s2
a.) What is the total time of travel?
b.) What total distance does the point move?
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A uniform cubical crate is 0.575 m on each side and weighs 900 N. It rests on the floor with one edge against a very small, fixed obstruction. At what height above the floor must a horizontal force of 625.0 N be applied to the crate to just tip it?
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Two rectangular pieces of plane glass are laid one upon the other on a table. A thin strip of paper is placed between them at one edge, so that a very thin wedge of air is formed. The plates are illuminated at normal incidence by 542nm light from a mercury-vapor lamp. Interference fringes are formed, with 14.0fringes/centimeter .
Find the angle of the wedge.
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A spacecraft with a proper length of 350 m passes by an observer on the Earth. According to this observer, it takes 0.780 µs for the spacecraft to pass a fixed point. Determine the speed of the spacecraft as measured by the Earth-based observer.
Please show how you arrive at your answer!
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