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SUVAT for throwing something horizontally

How do you find the height something is thrown from when you know that it has been thrown horizontally with projection speed 24m/s and hits the ground 4 seconds later ?

Reply 1

Joinedup

Original post by Elliewhitehall

How do you find the height something is thrown from when you know that it has been thrown horizontally with projection speed 24m/s and hits the ground 4 seconds later ?

How far would an object fall under acceleration due to gravity in 4 seconds?

Reply 2

Muttley79

Original post by Elliewhitehall

How do you find the height something is thrown from when you know that it has been thrown horizontally with projection speed 24m/s and hits the ground 4 seconds later ?

What have you done so far? Please post your working.

Reply 3

Elliewhitehall

Original post by Muttley79

What have you done so far? Please post your working.

I have listed the numbers I know. u = 24 , a = 9.81 , t = 4 . I need to know the distance the ball falls after being thrown. I have tried s = ut + 1/2at^2 and that gave the wrong answer (174.5m). The correct answer is 78.5m

Reply 4

Muttley79

Original post by Elliewhitehall

It is thown horizontally, gravity acts vertically ...

vert taking downwards as +
u = what ?
a = 9.8
t = 4

Reply 5

Elliewhitehall

Original post by Muttley79

It is thown horizontally, gravity acts vertically ...

vert taking downwards as +
u = what ?
a = 9.8
t = 4

U = 24 ?

Reply 6

Elliewhitehall

Original post by Elliewhitehall

U = 24 ?

I did it. U = 0 so s = 74.5m

(edited 6 years ago)

Reply 7

Elliewhitehall

Original post by Elliewhitehall

How do you find the height something is thrown from when you know that it has been thrown horizontally with projection speed 24m/s and hits the ground 4 seconds later ?

How would I find the horizontal distance?

Reply 8

Joinedup

Original post by Elliewhitehall

How would I find the horizontal distance?

How far does a projectile travelling at 24m/s go in 4 seconds?

Reply 9

Muttley79

Original post by Elliewhitehall

I did it. U = 0 so s = 74.5m

Yes, if it's thrown horizontally then the vertical component of velocity is zero.

Reply 10

Elliewhitehall

Original post by Joinedup

How far does a projectile travelling at 24m/s go in 4 seconds?

So you would just do it as if the horizontal component was a single particle moving in a straight line horizontally?

Reply 11

Joinedup

Original post by Elliewhitehall

So you would just do it as if the horizontal component was a single particle moving in a straight line horizontally?

Yeah - you treat the vertical and horizontal components of the motion independently.
vertical component is subject to constant acceleration due to gravity
horizontal component is constant speed

if the launch angle isn't vertical or horizontal you'll have to do an additional bit of trig to resolve the initial velocity into it's vertical and horizontal components.

Reply 12

gurungg48

Check the attachment

Original post by Elliewhitehall

How do you find the height something is thrown from when you know that it has been thrown horizontally with projection speed 24m/s and hits the ground 4 seconds later ?