The contact time is the time for which two colliding objects are in contact with each other.Contact time is not the same as impact time. If the collisions results in the two objects sticking together the duration of the impact force is not the same as the contact time.The shorter the contact time, the greater the impact force The impact time is obtained from: s = ½(u + v)t
Impact time is the duration of the impact force.
| impact time t | = | 2s u + v |
| acceleration a | = | v - u t |
| impact force F | = | m a |