# Projectile Motion Ball throw Question

## Homework Statement

Someone throws a ball 1m from the ground at a 30 degree angle to the corner of the room 8m away and elevated by 1m. Find the initial velocity of the ball.

s=ut+1/2at^2

## The Attempt at a Solution

So i broke it up into vector components in order to find the time for each component, ihave this so far...
Vertical
0=u(cos30)t+1/2*-9.8*t^2
Horizontal
8=u(sin30)+1/2*0*t^2
I dont really know where to go from here after i have rearranged to find the time of each component, i thought i could use simultaneous equations to find the inital velocity but i'm unsure of how i would go about it and my algebra isn't too good.
Please let me know what you would do after this or if there is some formula i may have missed out on that could help me solve this question.

## Answers and Replies

cnh1995
Homework Helper
Gold Member
elevated by 1m
Does that mean the corner is also 1m above the ground, like the point of projection? In that case, 8m distance becomes the range of projectile. Use the formula for range of projectile.

SteamKing
Staff Emeritus
Science Advisor
Homework Helper

## Homework Statement

Someone throws a ball 1m from the ground at a 30 degree angle to the corner of the room 8m away and elevated by 1m. Find the initial velocity of the ball.

s=ut+1/2at^2

## The Attempt at a Solution

So i broke it up into vector components in order to find the time for each component, ihave this so far...
Vertical
0=u(cos30)t+1/2*-9.8*t^2
Horizontal
8=u(sin30)+1/2*0*t^2
I dont really know where to go from here after i have rearranged to find the time of each component, i thought i could use simultaneous equations to find the inital velocity but i'm unsure of how i would go about it and my algebra isn't too good.
Please let me know what you would do after this or if there is some formula i may have missed out on that could help me solve this question.
Are you sure you used the correct components for the initial velocity in the vertical and horizontal directions?

Draw a picture.

Are you sure you used the correct components for the initial velocity in the vertical and horizontal directions?

Draw a picture.

Yeaaa you made an error with the components on the vertical and horizontal directions. Drawing a diagram for the components always helps. Make it a habit to make sure your components are right.