A velocity selector uses a fixed electric field of magnitude E and the magnetic field is varied to select particles of various energies. If a magnetic field of magnitude B is used to select a particle of a certain energy and mass, what magnitude of magnetic field is needed to select a particle of equal mass but twice the energy?
a. 0.50 B
b. 1.4 B
c. 2.0 B
d. 0.71 B
e. 1.7 B
d
You might also like to view...
If you tried to use a diverging lens as a magnifier by placing the object at the focal point, what type of image would be produced?
A. Upright and larger than the object B. Inverted and larger than the object C. Inverted and smaller than the object D. Upright and smaller than the object
Suppose that, for some unknown reason, the core of the Sun suddenly became hotter. Which of the following best describes what would happen?
A) Higher temperature would cause the rate of nuclear fusion to rise, which would increase the internal pressure, causing the core to expand and turn the Sun into a giant star. B) Higher temperature would cause the rate of nuclear fusion to rise, which would increase the internal pressure, causing the core to expand and cool until the fusion rate returned to normal. C) Higher temperature would cause the rate of fusion to fall, decreasing the internal pressure and causing the core to collapse until the rate of fusion returned to normal. D) The higher temperature would not affect the fusion rate but would cause the core to expand and cool until the temperature returned to normal, with the core at a new, slightly larger size.
A 120-m long metal wire having a resistivity of 1.68 × 10-8 ? ? m has a resistance of 6.0 ?. What is the diameter of the wire?
A) 0.065 mm B) 0.65 mm C) 0.65 cm D) 0.65 m
Two tiny beads are 25 cm apart with no other charges or fields present. Bead A carries 10 µC of charge and bead B carries 1 µC. Which one of the following statements is true about the magnitudes of the electric forces on these beads?
A) The force on A is exactly equal to the force on B. B) The force on B is 10 times the force on A. C) The force on A is 100 times the force on B. D) The force on B is 100 times the force on A. E) The force on A is 10 times the force on B.