Deceleration is simply negative acceleration, meaning it is the process of slowing down. It's quantified with the same units as acceleration, \( \text{m/s}^2 \), but it acts in the direction opposite to the motion.When calculating deceleration, we use the formula:
- \( a = \frac{v_f - v_i}{t} \)
where:
- \( v_f \) is the final velocity
- \( v_i \) is the initial velocity
- \( t \) is the time interval over which the change occurs
In the exercise example, the skater is initially moving at 2.40 m/s and comes to rest, so the final velocity is 0. By inserting these values into the deceleration formula, we understand how quickly they slow down. The deceleration value is crucial for determining how strong the frictional force needs to be to stop the skater within the specified time.