Why might scientists measure the mass of object rather than the weight of an object?

If forces acting on an object are unbalanced, which factors may result fron an unbalanced force? check all that apply

Alfred pushes on a heavy box, but cannot move it. the box has a lot of inertia motion friction gravity

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.