A car drives along a dual carriageway at 96 km h−1. The driver sees a speed limit sign approaching and applies the brakes to decelerate to a speed of 48 km h−1. Given that the deceleration is 2.68 m s−2 find the distance over which the brakes are applied. Formula I think to use is to basratardise this formula which uses potential energy to find the distance Which is Ek = ½ mv2 DeltaEg = mg Delta h Which equates to mg Delta h = ½ mv2 which would change to delta h = v²/2g I would change h for d=distance V² would equal 48 km h−1 converted to m sˉ¹ g would I would change to a for acceleration (deceleration)= 2.68 m s−2 so it would be delta d = v²/2a can I do this? My thinking is that energies are conserved so it would be ok to do this?