The objective of this lab is to comprehend the protection of direct force through the perception of versatile and inelastic crashes. Also, decide the change in and exchange of mechanical vitality in impacts because of fluctuating versatility and apply the law of protection of force to take care of issues of crashes. First of all, we found the mass of the cart without adding the weight on and also with adding it which was 500g. we found the results for the elastic first and then the two inelastic. For the elastic we found the following results: Pi= 147g*m/s Pf= 146 g*m/s KEi= 20.9J KEf= 21.5J. After adding the 500g to the cart we got different results which are they Pi= 199g*m/s Pf= 68.6g*m/s KEi= 19.9J KEf= 4.47J. On the other hand, the inelastic has the same steps as the elastic, but we got different results which are they Pi= 276g*m/s Pf= 87.1g*m/s KEi= 35.9J KEf= 52.6J. After adding the 500g to the cart we got the following results Pi= 369g*m/s Pf= 58.1g*m/s KEi= 68.2J KEf= 10.7J. Finally, what we figure out is that the results that we got in the elastic is close to each other, but for the inelastic is the opposite the results are far away from each other. Overall, we had some errors in our results like human and systematic errors.