A six-pole, lap-wound, 220 V, shunt-excited d.c.machine takes an armature current of 2.5 A when
unloaded at 950 r/min. When loaded, it takes an armature current of 54 A from the supply and runs
at 950 r/min. The resistance of the armature circuit is 0.18 ? and there are 1044 armature conductors...
For a hw problem, I am using a DC motor to turn a reaction wheel with a moment of inertia of 0.78125 kgm^2. The DC - motor has an inductance of L=0.5 H and a resistance of R=1 ohms. There is a damping ratio of b= 0.1 Nms. How do I find the electromotive force constant from that? Thanks!
For a hw problem, I am using a DC motor to turn a reaction wheel with a moment of inertia of 0.78125 kgm^2. The DC - motor has an inductance of L=0.5 H and a resistance of R=1 ohms. There is a damping ratio of b= 0.1 Nms. How do I find the electromotive force constant from that? Thanks!
I have an iPhone 3G. I'd like to know if there is an EMF detector for it. If there is none, can a software compass do the same job? Also maybe using the bending of wifi or cell phone waves might do instead. Any answers would be appreciated.
A pickup truck has a width of 78.8 in. If it is traveling north at 44 m/s through a magnetic field with vertical component of 30 µT, what magnitude emf is induced between the driver and passenger sides of the truck?