Q. A 70.0-kg astronaut pushes to the left on a spacecraft with a force F in "gravity-free" space. The spacecraft has a total mass of 1.0 × 104 kg. During the push, the astronaut accelerates to the right with an acceleration of 0.36 m/s2. Determine the magnitude of the acceleration of the spacecraft.

Q. A total electric charge of 4.50 nC is distributed uniformly over the surface of a metal sphere with a radius of 22.0 cm. The potential is zero at a point at infinity. Find the value of the potential at 45.0 cm from the center of the sphere.