Define an interface called Vehicle, which requires the following methods getName: returns a String getTopSpeed: returns an int getMaxPassengers: returns an int Note that the class Car implements this interface and is preloaded (in one of the following questions you will define this class)
For example:
Test
Vehicle v = new Car("BMW", 280, 5); System.out.println(v.getName()); System.out.println(v.getTopSpeed()); System.out.println(v.getMaxPassengers());
Results :
BMW
280
5
Test 2 :
Vehicle v = new Car("Smart", 150, 2); System.out.println(v.getName()); System.out.println(v.getTopSpeed()); System.out.println(v.getMaxPassengers());
Results :
Smart
150
2
In: Computer Science
Two capacitors C1 = 3.2 ?F, C2 = 13.5 ?F are charged individually to V1 = 19.0 V, V2 = 5.6 V. The two capacitors are then connected together in parallel with the positive plates together and the negative plates together.
1.Calculate the final potential difference across the plates of the
capacitors once they are connected.
2.Calculate the amount of charge (absolute value) that flows from
one capacitor to the other when the capacitors are connected
together.
3.By how much (absolute value) is the total stored energy reduced when the two capacitors are connected?
In: Physics
The rechargeable batteries for a laptop computer need a much smaller voltage than what a wall socket provides. Therefore, a transformer is plugged into the wall socket and produces the necessary voltage for charging the batteries. The batteries are rated at 9.0 V, and a current of 272 mA is used to charge them. The wall socket provides a voltage of 120 V.
(a) Determine the turns ratio of the transformer
|
Ns/Np = |
(b) What is the current coming from the wall socket?
Ip =
(c) Find the average power delivered by the wall socket and the
average power sent to the batteries.
Pp =
Ps =
In: Physics
Question
2 of 20
Current is caused by
voltage differences.
resistance.
capacitance.
none of the above.
Question
3 of 20
A battery with a potential difference of V connects to a resistor, and the resulting current is measured. You remove the battery, and a new battery with a potential difference of 2V is put in its place. As a result,
the current will double.
the resistance will double.
both the current and the resistance will double.
battery replacement will have no effect on the circuit.
Question
4 of 20
The definition of current is the
potential difference across an electrical component.
flow rate of charge through some point.
speed of charge through some point.
rate of energy dissipation by a resistor.
Question
5 of 20
Which device would cost more to run continuously for 1 hr?
100 W light bulb
A clock radio with an total resistance of 200 Ω that operates with a 120 V potential difference
A hand mixer with a total resistance of 120 Ω that draws 1 A of current
A television that uses a 120 V potential difference to draw 1.25 A of current
In: Physics
An exhaust fan systems consists of 4 parallel v-belts wrapped around driver pulleys A and driven pulley B with a diameter of 100 mm and 240 mm respectively. Coefficient of friction, μ between belt and pulleys is known as 0.25. Pulley groove, α has been design at an angle of 60°. The maximum permissible tension is 3860 N, cross-sectional area of the belt is A = 160 mm2 and density of belt’s material ρ = 1000 kg/m3. If the driver pulley A and driven pulley B rotates at a speed of 1800 RPM and 700 RPM individually due to slippages.
(i) Find the angle of contact of pulley A, given the pulley centre to centre distance is 1000 mm.
(ii) Calculate the tension distributed by centrifugal forces in one V-belt.
(iii) Deduce total power transmitted by the driver pulley A.
(iv) Deduce total power received by the driven pulley B.
(v) Find the belt slip percentage at pulley B
In: Mechanical Engineering
A three-phase asynchronous motor with squirrel cage
rotor is available with:
Voltage: 230/400 V
Frequency: 50 Hz
Number of Poles: 10
In addition, the following parameters of the equivalent circuit are
known:
R1 = 0.5 X1 = 3 R´2 = 0.8 X´2 = 3.5
Mechanical losses are considered to be negligible and the parallel
branch of the
equivalent circuit.
1. Draw the approximate equivalent circuit of the motor without the
branch in parallel.
2. Indicates the connection mode of the motor stator when connected
to a three-phase voltage network
Composed 400 V (i.e. 400 V line). Justify the answer.
3. What current will this motor draw at startup?
4. Considering that the slip at full load is 4%, calculate:
4.1. The absorbed current.
4.2. The developed mechanical power.
4.3. The useful torque.
4.4. The active power absorbed from the network.
4.5. Performance.
5. At what speed is the maximum torque obtained?
6. How much is the maximum torque worth?
In: Electrical Engineering
An exhaust fan systems consists of 4 parallel v-belts wrapped around driver pulleys A and driven pulley B with a diameter of 100 mm and 240 mm respectively. Coefficient of friction, μ between belt and pulleys is known as 0.25. Pulley groove, α has been design at an angle of 60°. The maximum permissible tension is 3860 N, cross-sectional area of the belt is A = 160 mm2 and density of belt’s material ρ = 1000 kg/m3. If the driver pulley A and driven pulley B rotates at a speed of 1800 RPM and 700 RPM individually due to slippages.
(i) Find the angle of contact of pulley A, given the pulley centre to centre distance is 1000 mm.
(ii) Calculate the tension distributed by centrifugal forces in one V-belt.
(iii) Deduce total power transmitted by the driver pulley A. (iv) Deduce total power received by the driven pulley B. (v) Find the belt slip percentage at pulley B
In: Mechanical Engineering
Design a single stage BJT amplifier with the following constraints:
This involves the following:
-DC and AC analysis and the frequency response of the amplifier.
-Use a 2N2222 transistor
-Power supply (VCC): 6 V
-An input impedance near to 3 kΩ
-Overall midband voltage gain of -30 V/V
-A load resistance of 2 kΩ
-The input signal has an RSignal of 500 Ω
-Choose a good Qpoint and select the coupling and bypass capacitors to obtain an fL-3dB of 100 Hz.
-The capacitors and resistors should have commercial values
-Part of the design requirement is that the amplifier will exhibit maximum symetrica1 swing in the voltage collector.
The Total Harmonic Distortion of the output voltage should be less than 5% when a sine wave with an amplitude of 5 mV is applied by the signal.
Determine the analytical fH-3dB of the final design of the amplifier. When the final design is completed, obtain the frequency response of the amplifier to verify the midband voltage gain, fL-3dB and fH-3dB.
In: Electrical Engineering
-The Moon orbits the Earth in an approximately circular path. The position of the Moon as a function of time is given by
| x(t) | = | r cos(ωt) |
| y(t) | = | r sin(ωt), |
where r = 3.84 108 m and ω = 2.46 10-6 radians/s. What is the average velocity of the Moon measured over the interval from t = 0 to t = 3.35 days? Find its magnitude, in m/s, and find its direction, given as an angle measured counterclockwise from the positive x-axis.
magnitude ???? m/s
direction ?????? ° counterclockwise from the +x-axis
-A space probe approaches a planet and goes into a low orbit. If the orbiting probe's velocity is
| vx | = | −v sin(ωt), |
| vy | = | v cos(ωt), |
| v | = | 7.57 103 m/s, |
| ω | = | 1.16 10-3 radians/s, |
what is the average magnitude of acceleration of the probe, in m/s2, if it remains in orbit for 22 minutes? answer in m/s
In: Physics
A molecule of mass 2.0×10-24Kg is moving along at a speed of 100±10 m/sec, where the ±10 m/sec is the statistical spread or uncertainty in the determination of its velocity or ∆v = 10 m/sec. The molecule is somewhat localized in space and is described by a travelling wave packet solution to the Schrödinger equation centered around x=0 at t=0 and moving in the positive x-direction.
In: Physics