Answer:
1200KJ
Explanation:
The heat dissipated in the rotor while coming down from its running speed to zero, is equal to three times its running kinetic energy.
P (rotor-loss) = 3 x K.E
P = 3 x 300 = 900 KJ
After coming to zero, the motor again goes back to running speed of 1175 rpm but in opposite direction. The KE in this case would be;
KE = 300 KJ
Since it is in opposite direction, it will also add up to rotor loss
P ( rotor loss ) = 900 + 300 = 1200 KJ
Answer:
Only Technician B is right.
Explanation:
The cylindrical braking system for a car works through the mode of pressure transmission, that is, the pressure applied to the brake pedals, is transmitted to the brake pad through the cylindrical piston.
Pressure applied on the pedal, P(pedal) = P(pad)
And the Pressure is the applied force/area for either pad or pedal. That is, P(pad) = Force(pad)/A(pad) & P(pedal) = F(pedal)/A(pedal)
If the area of piston increases, A(pad) increases and the P(pad) drops, Meaning, the pressure transmitted to the pad reduces. And for most cars, there's a pressure limit for the braking system to work.
If the A(pad) increases, P(pad) decreases and the braking force applied has to increase, to counter balance the dropping pressure and raise it.
This whole setup does not depend on the length of the braking lines; it only depends on the applied force and cross sectional Area (size) of the piston.
Answer:
<u>construction workers</u>
Explanation:
A construction worker is usually someone with the technical skills and abilities needed to manually construct physical infrastructures.
Since a walkway is an infrastructure, hiring skilled construction workers should perform the project of building the series of walkways within the large garden apartment.
Answer:
il(t) = e^(-100t)
Explanation:
The current from the source when the switch is closed is the current through an equivalent load of 15 + 50║50 = 15+25 = 40 ohms. That is, it is 80/40 = 2 amperes. That current is split evenly between the two parallel 50-ohm resistors, so the initial inductor current is 2/2 = 1 ampere.
The time constant is L/R = 0.20/20 = 0.01 seconds. Then the decaying current is described by ...
il(t) = e^(-t/.01)
il(t) = e^(-100t) . . . amperes