Three of the four designs DID lift the required mass. One design fell short. After reviewing the other designs, it is apparent that changing one feature will easily result in this group's success. What is that change?

Question

Three of the four designs DID lift the required mass. One design fell short. After reviewing the other designs, it is apparent that changing one feature will easily result in this group's success. What is that change?

Responses
A Remove the switch from the circuit.Remove the switch from the circuit.
B Replace the D-cell with a 9-volt battery.Replace the D-cell with a 9-volt battery.
C Use two nails instead of one for the core.Use two nails instead of one for the core.
D Wrap the 150cm wire tighter around the iron core.

Answer 1

Three of the four designs DID lift the required mass. One design fell short. After reviewing the other designs, it is apparent that changing one feature will easily result in this group's success. What is that change?

D - Wrap the 150cm wire tighter around the iron core.