A long straight wire (diameter = 2.0 mm) carries a current of 40 A. What is the magnitude of the magnetic field 1.5 mm from the axis of the wire?
a. 3.0 mT
b. 12 mT
c. 5.3 mT
d. 7.4 mT
e. 8.0 mT
c
You might also like to view...
Molecular Bonds: Van der Waals bonding is due to
A. the sharing of electrons between atoms. B. the transfer of electrons between atoms. C. unequal charge distribution around neutral molecules. D. atoms bonding to hydrogen molecules.
Two masses are connected by a string which passes over a pulley with negligible mass and friction. One mass hangs vertically and one mass slides on a frictionless horizontal surface. The horizontal surface has a coefficient of kinetic friction of 0.2. The vertically hanging mass is 4.00 kg and the mass on the horizontal surface is 6.00 kg. The acceleration of the 4.00 kg mass is
A. 1.98 
B. 2.74
C. 4.88
D. 6.73
E. 7.84
A giant star radiates energy at the rate of 3.0 × 1030 W, and its surface temperature has been measured to be 3000 K. Assuming that it is a perfect emitter, what is the radius of this star? (? = 5.67 × 10-8 W/m2 ? K4)
A) 7.8 × 1010 m B) 8.7 × 1010 m C) 1.4 × 1010 m D) 1.9 × 1011 m E) 2.3 × 1011 m
Which of the following statements is true?
a. A hot object contains a lot of heat. c. Objects do not contain heat. b. A cold object contains only a little heat. d. Statements a and b are true.