# Questions & Answers

Contents

- Find an explicit description of nul A by listing vectors that span the null space.
- A -10.0 nC point charge and a +20.0 nC point charge are 15.0 cm apart on the x-axis. Find the following:
- A particle moves along the curve y=2 sin(pi x/2). As the particle passes through the point (1/3, 1), its x-coordinate increases at a rate of sqrt{10} cm/s. How fast is the distance from the particle to the origin changing at this instant?
- Find the particular solution that satisfies the differential equation and the initial condition.
- Find an orthogonal basis for the column space of the matrix given below: