Question

A cannon is situated on the edge of a cliff that is 78m above the sea. A ball that is dropped straight down will hit the sea with a speed of 39m/s. if the cannon fires a shell horizontally at 260m/s, calculate the time for the shell to hit the water.

Answer 1

Let me give you the idea for this question.Whether the ball is fired horizontally or dropped the final velocity(In this case 39m/s) will be the same.Initial velocity is 0.So go for s=ut+.5at^2.Substitute in this equation the values and get the answer

Answer 2

To find 'a'(acceleration) you can use v^2-u^2=2as

Answer 3

change in d = v1(time) +1/2(acceleration)(time)^2 <- that equation? and alright. Thanks :)

Answer 4

yes that equation well notataions are different in different books.....