GENERAL PHYSICS II - PRACTICE EXAM I

 SUMMER  QUARTER 2002

 

 

1.         A 600 g mass is hung from a vertical spring. It oscillates up and down with a period of 0.500 s. The mass is pushed up from its equilibrium position (y = 0) by 10.0 cm and released.

(a)        Write an equation for the vertical position of the mass as a function of time, t, after the mass was released.

(b)        What is the maximum speed of the mass?

(c)        What is the spring constant, k, of the spring?

(d)        What is the maximum net force exerted on the mass?

(e)        If the mass were given an initial downward speed of 1.00 m/s at t = 0, instead of being released from rest, what would be the new answers for parts (b) and (c).

 

 

2.         Point charges of the following values are placed at the positions:

A ( qA = + 1.0 x 10-5 C,  xA = 0    ,  yA = 0     )

B ( qB = - 2.0 x 10-5 C,  xB = 10 cm,  yB = 0     )

C ( qC = + 3.0 x 10-5 C,  xC = 10 cm,  yC = 10 cm )

Find the force, F, on each charge exerted by the other two charges.

 

 

3.         A charge of Q = +10-6 C is uniformly distributed around a circular ring of radius R = 30 cm. The ring is in the yz plane with its center at the origin. The axis of the ring is the x-axis.

a)                  What is the linear charge density, λ, of the circular ring?

b)                  Find the magnitude and direction of the electric field vector, E, along the axis of the ring at the point x = 40 cm.

c)                  What point charge q could be placed at the center of the ring, x = 0, to make the electric field zero at x = 40 cm?

 

 

4.         A very long insulating cylinder of radius R1 has a charge per unit length of λ distributed uniformly throughout the cylinder. The cylinder is surrounded by a concentric cylindrical conducting shell of inner radius R2 and outer radius R3. The shell contains a charge per unit length of -5λ. Determine the direction of the electric field and its magnitude as a function of r, the distance from the center of the cylinder for:

(a)        0 < r < R1

(b)        R1 < r < R2

(c)        R2 < r < R3

(d)        R3 < r

(e)        What is the charge per unit length on the inner and outer surfaces of the conducting shell?