1) Harry Hopeless averages 40km/h for the first half of his car trip. How fast should he drive on the remaining half of the trip to have an average speed of 80km/h for his trip?
2) You drive to the city at an average speed of 40km/h and return at an average speed of 60kmh/ Find your average speed for the entire trip? Explain why the answer is not 50km/h
3)A train moves at a constant speed of 60Km/h toward a station 30km away. At that moment Fanny Fastbird leaves her perch on the locomotive and flies toward the station at a constant speed of 100km/h relative to the ground. When the bird reaches the station, she immediately turns around and flies back to the train at the same speed. What reaching the train she again immediately turns around and flies back to the station, repeating the process until the train passes the station. What total distance is traveled by the bird?
4) When Valerie VolleyBaller jumps to spike a ball, she rises a total of 2.0m in the air after accelerating through .5m (from crouch to full extension). What is her acceleration.
Thanks to whoever took the time to read all that and try to help me. I have a beginner so I'd appreciate it if whoever answers can go step by step.
X= x0+v0t+at/2 X= Final position x0=Initial position v0=Initial Velocity/speed t=time a=acceleration
V^2=v0^2+ 2a (x-x0)
The Attempt at a Solution
Out of 30 these were the 4 ones I couldn't do. I don't even know where to start. I'm very new to physics and my teacher isn't helping much.