# What does jerking during deceleration mean?

your foot is on the clutch too long

### Use Newton first law of motion to explain why airbags in cars areimportant during head-on collisons?

### What is the formula for deceleration?

The first answer is backward. Acceleration = (final velocity - initial velocity)/total time. For deceleration the formula is the same, the answer will just be negative. Agreed. In physics, there is no "deceleration", only negative acceleration. a = Δv / Δt There is no equation for "deceleration" as suggested below. Deceleration=(original velocity-final velocity)/Time Deceleration In Motion Deceleration = inital speed - final speed / total time taken