When running at its operating speed, a 215-V dc motor with an armature whose resistance is 1.20 Ω draws a current of 25.0 A. What is the back emf of the motor when it is operating normally?

What is the relationship between the wavelength of a wave and it's energy?

Imagine you are riding on a yacht in the ocean and traveling at 20 mph. you then hit a golf ball at 100 mph from the deck of the yacht. you see the ball move away from you at 100mph, while a person standing on a near by beach would observe your golf ball traveling at 120 mph (20 mph + 100 mph). now imagine you are aboard the hermes spacecraft traveling at 0.1c (1/10 the speed of light) past mars and shine a laser from the front of the ship. you would see the light traveling at c (the speed of light) away from your ship. according to einstein’s special relativity, how fast will a person on mars observe the light to be traveling? a) 0.1c (1/10 the speed of light) b) c (the speed of light) c)1.1c (c+0.1c)

Which body part transports oxygen removes waste materials in carries nutrients to the body as part of the circulatory system