Answer:
let M be the mass of brick
let m be the mass of the pebble
.5M(3)^2 =KE
.5m(5)^2= KE
.5M9 = .5m25
9M = 25m
(9/25)M = m
Answer:
Go to K.han Academy and look up High School Physics on there. Other than that You.Tube has some physics curriculums which probably have practice questions. If not you could just pause the video and see if you can answer the questions they're going over yourself. Also, searching up "Physics Worksheet" and such may help.
Average speed = total distance / total time
total distance = 40 + 20 = 60km
total time taken = 10 + 5 = 15 minutes
Average speed = 60/15 = 4km/min
