An astronomer is shooting a green laser with a wavelength of 540 nm at an asteroid. the light reflects off the asteroid and is reading as 538.9 nm.
a. is the asteroid moving toward from the astronomer? how can you tell?
b. what is the speed of the asteroid?

Ais useful when you need a simple machine to you separate two things. a. lever b. screw c. pulley d. wedge

Amachinist turns the power on to a grinding wheel, at rest, at time t = 0 s. the wheel accelerates uniformly for 10 s and reaches the operating angular velocity of 96 rad/s. the wheel is run at that angular velocity for 40 s and then power is shut off. the wheel slows down uniformly at 1.5 rad/s2 until the wheel stops. in this situation, the time interval of deceleration is closest to:

Which compound is held together by the electrostatic force between two ions? a. co2 b. cci4 c. h2s d. mgf2