Question

Maglev (magnetic levitation) trains float above their tracks. Electromagnets are used to make these trains levitate and move. The image below models how a maglev train levitates. The like poles of electromagnets repel each other and cause the train to float above the track.


Image courtesy of the U.S. Department of Energy

Ms. Turner and her students want to build a working model of a maglev train. They made four electromagnet prototypes, and they conducted several tests on the prototypes. They will use the results shown below to create a final electromagnet design.

Prototype Maximum
Weight That can
be Supported (kg) Battery
Life (h) Levitation
Height of Test
Magnet (mm)
W 6 10 1
X 6 6 1.1
Y 6 5.5 1.2
Z 6 4.5 4.5

Combining the strengths of which two prototypes would most likely lead to a new design that has an optimized battery life and levitation height combination?
A.
X and Y
B.
W and Y
C.
W and Z
D.
X and Z

Answer 1

C. W and Z

W has the best battery life (10 h) and Z has the greatest levitation height (4.5 mm), so combining their strengths would most likely optimize both battery life and levitation height.