Answer:
Check the explanation
Explanation:
C(x) = 0.06x^2 - 6x + 218
Its a quadratic function , minima would occur at vertex.
x is no. of digital cameras
x = -b/2a = -(-6/2*0.06) = 50 cameras
Minimum marginal cost : C(50) = 0.06(50)^2 - 6*50 + 218 = $ 68
The synchronous speed (rpm) equals 60 times the frequency divided by the number of pole pairs. For 50Hz, a two-pole motor will have a synchronous speed of 3000 rpm, a four-pole motor of 1500 rpm.
The actual speed is a few percent lower due to the slip of the asynchronous motor.
The slip increases with the torque, typical values are 5–10%. The rated speed for a four-pole motor at 50Hz will thus be something like 1360 rpm. At no-load, the slip is very small.