The coefficient of friction between a 0.17 kg puck and and the ice is μk = 0.15. If the puck leaves a hockey stick traveling at 20 m/s, what is its speed when it reaches the goalie 15 m away? How much time does the goalie have to react? Assume the puck travels on the ice the whole time.

What is the internal energy of 4.00 mol of diatomic nitrogen gas n2 at 455k

Mutt and jeff are running along a path each pushing a cart loaded with rocks. if mutt's wagon has a mass two times greater than jeff's and they want to stay together, arriving at their destination at the same time, what must happen? a) jeff should slow down so mutt can catch up. b) mutt must use half as much force to push his cart. c) mutt must use twice as much force to push his cart. d) mutt and jeff will use the same force, but mutt will take bigger steps.

Which accurately compares concave and convex lenses?