Answer:
They can be seen from a distance of 4.372 kilometers.
Explanation:
Using the Reyligh creterion for diffraction through a circular aperture we have
where symbol's have their usual meaning
thus applying values we get


Capacitors function is to store up electricity and release it when the current is flowing. When there is no current, Capacitors still have electricity stored in them and can be discharged accidentally if something conductive touches them.
Answer:
37 W
Explanation:
Power is the time rate of dissipation or absorbing energy. The power supplied or absorbed by an element is the product of the current flowing through the element and the voltage across the element. Power is measured in watts. If the power is positive then it is absorbed by the element and if it is negative then it is supplied by the element.
Power = voltage * current
For element A: Power = 36 V * -4 A = -144 W
For element B: Power = -20 V * -4 A = 80 W
For element C: Power = -24 V * 4 A = -94 W
For element D: Power = -80 V * -1.5 A = 120 W
For element E: Power = 30 V * 2.5 A = 75 W
The total power developed in the circuit = sum of power through the element = (-144 W) + 80 W + (-94 W) + 120 W + 75 W = 37 W
Answer: 2.7 x 10^5 joules
Explanation:
Given that:
Time taken = 3 minutes
convert time in minutes to seconds
(Since 1 minute = 60 seconds
3 minutes = 3 x 60 = 180 seconds)
Power of toaster = 1500 watt
Work done by the toaster = ?
Recall that power is the rate of work done per unit time
i.e Power = work/time
work = Power x Time
Work = 1500 watt x 180 seconds
Work = 270000J
Place the result in standard form
270000J = 2.7 x 10^5J
Thus, 2.7 x 10^5 joules of work is done by the toaster.
An electrical generator and motor are two machines that operate oppositely.
An electrical generator uses mechanical energy, converting it to produce electrical energy. This mechanical energy is provided in most cases from a spinning/rotating action in which a wire or loop of wire spins in a magnetic field. This causes the wire to move sharply through the magnetic field, causing current to flow, and in turn, creating electricity.
An electrical motor does the opposite, but uses the same principles, converting electrical energy to produce mechanical energy. The motor will have an alternating current (AC) moving through pairs of magnets, producing a rotating magnetic field. This causes the motor's central rotor to spin, powering whatever machinery it is hooked up to.