James and John are interested in diving off an overhang into a lake. John takes a running start and jumps with an initial horizontal velocity of 25 m/s. James simply drops straight down from the edge. Neglecting air resistance, what will have when they reach the lake below?
Answers
Answer:James and John should take the same time in reaching the lake with John having greater velocity.
Explanation:James falls straight down , hence we consider him as a freely falling body.
T (james) =(2*height of cliff above lake/acceleration due to gravity )^1/2
Since John has a horizontal velocity of 25 m/s, and he doesn't possess any vertical velocity, he will be moving downwards solely sue to gravity and since he must cover the same height as James , his time of flight remains the same (as mentioned above). However , just as he reaches the lake, he will be having a vertical velocity of value (acceleration due to gravity(g)*time of flight(t)) the vector sum of these two velocities gives you the magnitude of his final velocity
V (John)=((25)^2 + (gt)^2)^(1/2).
hope it helps.