Question

a student makes a prototype of an electromagnet that can pick up a maximum of 6 paper clips. the student modifies the prototype. the c
a test if the electromagnet can release 3 paper clips.
b test if the electromagnet can pick up 7 paper clips.
c test if the electromagnet can pick up 6 paper clips from a farther distance.
d test if the electromagnet can pick up 8 paper clips when not connected to a power source.
e test if the electromagnet can release 6 paper clips when disconnected from a power source.
which tests on the modified prototype of the electromagnet will help the student check if the strength of the electromagnetic increases?
tests a and b
tests b and c
tests c and d
tests d and e

Explanation:

The strength of an electromagnet can be gauged by its ability to pick up more objects (test B - picking up 7 paper - clips instead of 6) and its ability to pick up the same number of objects from a farther distance (test C). Releasing paper - clips (test A) doesn't measure strength directly. An electromagnet needs a power source to work, so tests D and E are not valid for measuring its strength.

Answer:

B. tests B and C