Help super urgent plz 😭 mechanics

Alevelhelp.1

Help I don’t get why the 1.4 vertical distance is negative

for part b

(edited 10 months ago)

Reply 1

old_engineer

Original post by Alevelhelp.1

Help I don’t get why the 1.4 vertical distance is negative for part b

They're using the point where the ball is hit as the height datum. The ball is caught 1.4m below that, which will be represented as a displacement of -1.4m is upwards is taken as positive.

Reply 2

ivanqd

The original height is 1.6, since the ball is caught at 0.2 above the ground and we have assumed up as positive, then the displacement of the ball is -1.4 meters. This assumption is seen in part a, where g is negative and the initial velocity is 22m/s at an angle in the positive direction