The spectral type that denotes the coolest regular star is . Objects cooler than this are not considered stars, but are given the name . These objects are very hard to observe because they are very faint in visible light, and put out most of their energy as . Eventually, new spectral types were used for these objects; the warmest of them are given spectral type __, while the coolest of them are given spectral type ___

In which of the following is positive work done by a person on a suitcase

Visualize the problem and identify special cases first examine the problem by drawing a picture and visualizing the motion. apply newton's 2nd law, ∑f⃗ =ma⃗ , to each body in your mind. don't worry about which quantities are given. think about the forces on each body: how are these consistent with the direction of the acceleration for that body? can you think of any special cases that you can solve quickly now and use to test your understanding later? one special case in this problem is if m2=0, in which case block 1 would simply fall freely under the acceleration of gravity: a⃗ 1=−gj^.

Arope has one end tied to a vertical support. you hold the other end so that the rope is horizontal. if you move the end of the rope back and forth with a frequency of 4 hz, the transverse wave you produce has a wavelength of 0.5 m. what is the speed of the wave in the rope?