Question

a canon shell is launched from a cliff 400m above a plain at a velocity of 250ms at 60 above the horizontal.
1. initial ux=216.5ms uy=125
2.maximum height is 411.046 m
3.total time of flight is 31.25sec
4. range is 3906.25m
5. the impact velocity of the shell ? how do i find this?

Answer 1

i have no idea im sorry

Answer 2

i hope you know the basic equations of motion. The trick is to find the horizontal and vertical components of velocity separately and apply the equations of motion on them

Answer 3

yea i am doing that i am not finding a bigger angle

Answer 4

than 60'

Answer 5

i think 60 is the height isn't it

Answer 6

noo its an angle height is 400 m but total height is 411.046

Answer 7

one simple way that I can think of:
u know ux will remain unchanged as there is no acceleration in the x direction
maximum height is given and at maximum height uy =0

Answer 8

so you can find vy (velocity in y direction at the point of impact) using
v^2 = u^2 + 2as

Answer 9

u already know vx (=ux) and you will find vy
you can easily find the velocity at the point of impact

Answer 10

you can additionally find the angle at which it strikes the ground if you would like to

Answer 11

uy=216.5 ay=-9.8ms t =31.25

so vy = uy +at

vy= 216.5+ (-9.8) 31.25 = -89.75ms

Answer 12

no

Answer 13

use v^2 = u^2 +2 as
where s is the max. height

Answer 14

and uy =0 at max height

Answer 15

vy^2 = 2 (9.8) *411.046

Answer 16

the same answer is coming

Answer 17

see i wanna find an angle tan -1 ( 89.75/125)

which shuld be bigger than 60

Answer 18

oh yes you will get the same

Answer 19

and both are right

Answer 20

it gives 112 degrees i gues

Answer 21

no 35

Answer 22

let me check

Answer 23

yeah right 35......but why do you say the angle should be greater than 60

Answer 24

i dunno my teacher said that! -_-

Answer 25

i ll check with him tomorrow thnx for the help !

Answer 26

first of all i believe that 60 above the horizontal cannot be mentioning the angle but distance above the horizon

Answer 27

u can check for yourself by finding the angle by tan-1(uy/ux)