1. If the coefficient of friction between your running shoes and the gym floor is 0.90, what is the smallest circle (radius) that you could run at 6.2 m/s without slipping? Be sure to include a FBD to help you analyze this problem!

2.A 4.0 kg cart moving at 5.0 m/s[R] collides head-on with a 2.0 kg cart moving at 4.0 m/s[L]. Their collision is cushioned by a linear elastic spring between them.

a. What is the total energy of the system before the collision?

b. At minimum separation, what is the velocity of each cart? (Hint: @ min. sep. v1 ' = v2 ' = vmin )

c. Calculate the total kinetic energy at minimum separation.

d. If the force constant of the spring is 900 N/m, what is its maximum compression during the collision?

3. A positive charge of +3.2 x 10 -6 C experiences an electric force of magnitude 4.0 N, acting to the left. What is the magnitude and direction of the electric field at that point?

4. Calculate the electric field intensity midway between two negative charges of 4.3 x 10 -9 C and 8.6 x 10-9 C that are 20 cm apart. Include a diagram of the situation.

5. Two 2.0 g spheres are attached to each end of a silk thread 1.20 m long. The spheres are given identical charges and the midpoint of the thread is then suspended from a point on the ceiling. The spheres come to rest in equilibrium, with their centres 15 cm apart.

a. Draw a diagram of the situation.

b. Draw a FBD of one of the spheres.

c. What is the magnitude of the charge on each sphere?

6. A small body of unknown charge, travelling 6.1 x 10 5 m/s, enters a 0.40 T magnetic field directed perpendicular to its motion. a. If the particle experiences a force of 9.0 x 10 -4 N, what is the magnitude of the charge?

b. If the object is sent into the magnetic field so that its velocity makes an angle of 30.0 with the magnetic field, by how much will the magnetic force be reduced?

7. An electron of mass 9.11 x 10 -31 kg travels perpendicularly through a magnetic field of strength 6.8 x 10-5 T at a speed of 3.4 x 10 5 m/s. What is the radius of the path of the electron?