Question

1. You are driving down the freeway at a constant 60 mph (26.8 m/s)·There is a truck in tot of you, and you estimate that every second you get 1 m closer to the truck. How fast is the truck going (in miles per hour)? 2. What is the velocity of the truck relative to you? Take the forward direction (the direction you are going in) to be positive 3. You are on an airplane and the flight screen informs you that your airspeed is 550 mph and your speed relative to the ground is 510 mph. What is the velocity (including direction) of the air around the plane (that is, the wind), relative to the ground? 4. Is there any mechanics experiment that you could perform inside the plane that would tell you the plane's velocity?

Answer 1

Airspeed = V_relative to air = 550 mph = V_airplane - V_air = 550 mph V_airplane w.r.t ground = V_airplane - V_ground = 510 mph subtracting (1) from (2) V_airplane - V_ground = 510 V_airplane - V_air = 550 V_air - V_ground = -40 mph There is no such experiments which would fell us the speed of airplane, because all the bodies inside the plane will be seen from the reference frame of plane The observer himself will be at the speed of plane \r\n 'd' is decreasing at the rate of 1m per second Thus, d(d)/dt = 1 m/s which will be the relative velocity of car with respect to the truck Because the distance is decreasing speed of truck is less than of my car by 1 m/s Therefore velocity of truck = 26.8 - 1 = 25.8 m/s Because truck is slower it means it is actually coming closer, so if I consider my car to be at rest, the truck