[Tulian]

Just wondering why the s=d/t formula can't be used for part 2 of this question ?

The time in the first part was 4.16

I got the time, and speed, do distance= 5*4.16 = 20.8 , I know I could use suvat but not sure why this method couldn't be used as I get it wrong.

[ghostwalker]

(Original post by Tulian)
Just wondering why the s=d/t formula can't be used for part 2 of this question ?

The time in the first part was 4.16

I got the time, and speed, do distance= 5*4.16 = 20.8 , I know I could use suvat but not sure why this method couldn't be used as I get it wrong.

s=d/t is for when you have constant speed (or average speed).

In this situation you have the speed at the start of the motion, but it's changing as the object is decelerating.

[Vulpes]

(Original post by Tulian)
Just wondering why the s=d/t formula can't be used for part 2 of this question ?

The time in the first part was 4.16

I got the time, and speed, do distance= 5*4.16 = 20.8 , I know I could use suvat but not sure why this method couldn't be used as I get it wrong.

s = d/t can only be used for objects travelling at a constant speed. The block B in this case is decelerating.

Use s = ut + 0.5 at^2 where:

s = ?
u = 5
a = -1.2
t = 4.17

(before anyone points it out, im just too lazy to type in the units above)

[Tulian]

Thanks alot

[najinaji]

(Original post by Tulian)
x

Was too late to help out, but I just wanted to wish you luck for your exam.