Question

   A free electron and a free proton are exactly 1.3 cm apart.

Find the magnitude of the acceleration of the proton.

Express your answer with the appropriate units.

Find the magnitude of the acceleration of the electron.

Express your answer with the appropriate units.

Hearing loss. Person A can barely hear a sound at a particular frequency with an intensity level of 2.4 dB. Person B, who has hearing loss, can barely hear a 14.8 dB tone with the same frequency.

Find the ratio of sound intensities at these two hearing thresholds.

Two Ping-Pong balls each have a mass of 2.5 g and carry a net charge of 0.400 μC . One ball is held fixed.

At what height should the second ball be placed directly above the fixed ball if it is to remain at rest there?

Express your answer to two significant figures and include the appropriate units.

h =     

Three charges are fixed in the x−y plane as follows: 1.6 nC at the origin (0, 0); 2.5 nC at (0.80 m , 0); –1.9 nC nC at (0, 1.10 m ).

Find the force acting on the charge at the origin.

Express your answers using two significant figures. Enter the x and y components of the force separated by a comma.

Three point charges are placed on the x-axis as follows: 20 μC at x=0; 32 μC at x=0.60m; and -10 μC at x=1.2m.

Find the net force on the 20 μC point charge. Assume the direction of the x-axis as positive.

Express your answer to two significant figures and include the appropriate units.

F1 =

Part B

Find the net force on the 32 μC point charge.

Express your answer to two significant figures and include the appropriate units.

F2 =

Part C

Find the net force on the -10 μC point charge.

Express your answer to two significant figures and include the appropriate units.

F3 =

Two point charges, –10 nC and +18 nC , are held fixed a distance 0.60 m apart. Assume that both charges lie on x-axis, for the -10 nC x = 0 and for the +18 nC charge x = 0.60 m .

Where can a +20 nC charge be placed so that the net force on it is zero?

Express your answer to two significant figures and include the appropriate units.

x =

Part B

Repeat part A if the third charge is –20 nC.

Express your answer to two significant figures and include the appropriate units.

Answer 1