A 16 gram mass is moving in + x-direction at 30 cm/s, while a 4.0 gram mass is moving in the -x direction at 50 cm/s. They collided head on and stick together. Find their velocity after collision. Assume negligible friction.

3. a particle with initial velocity v⃗ 0=(5.85×103m/s)j^ enters a region of uniform electric and magnetic fields. the magnetic field in the region is b⃗ =−(1.35t)k^. you can ignore the weight of the particle. a. calculate the magnitude of the electric field in the region if the particle is to pass through undeflected, for a particle of charge +0.640 nc.