A_ is one vector , Which has the same effect on a body as the tow or more vectors that are actually acting in that body . It starts at the beginning of the first vector and ends at the end of the last one ?​ Please help me

A10.0 kg cart and a 15kg cart are locked together with a compressed spring between them. they are then released so that the spring pushes the two carts apart. the 10.0 kg cart is moving at 4.5 m/s afterward. how fast is the 15kg cart moving? 3.0 m/s 2.0 m/s 4.5 m/s 5.0 m/s

When the displacement of a mass on a spring is 12a the half of the amplitude, what fraction of the mechanical energy is kinetic energy? at what displacement, as a fraction of a, is the mechanical energy half kinetic and half potential?

A36,287 kg truck has a momentum of 907,175 kg • . what is the truck’s velocity