Question

1. For a proton to pass undeflected in a region where the electric field is 0.5 N/C and a magnetic field of 1.25 x 10T , its speed must be?
2. Consider a spring used as a solenoid with a magnetic field of 0.25 T. What is the magnetic field if the spring is stretched to twice its original length?

a. 0.125 T b. 0.25 T c. 0.5T d. 1.0T

what is the magnetic field if the spring is compressed to half its original length and the current is increased to twice its original value?

a. 0.125T b. 0.25T c. 0.5T d. 1.0T

1. When particle of charge q and mass in enters a region of constant magnetic field traveling with a velocity that os perpendicular to the field, the orbit will be a/an.

a. Circle b. Ellipse c. Helix d. Straight line

1. Which of the following is not about two parallel wires carrying currents in the same direction?

a. They repel each other

b. They attract each other

c. The magnetic field in one wire exerts a force on the other wire

d. The forces exerted by the wires on one another from an action reaction pair.

Answer 1

1)

$$v=\frac{0.5}{1.25\cdot10^{-4}}=4000\frac{m}{s}$$

2) Answer: a. 0.125 T 

3) Answer: a. Circle

4) Answer: b. They attract each other