What is the spring constant of a bungee cord that stretches an additional 1.2 m when 100 N of force are applied?

A.115 N/m
B.83.3 N/m
C.0.012 N/m
D.98.8 N/m

Question

What is the spring constant of a bungee cord that stretches an additional 1.2 m when 100 N of force are applied?

A.115 N/m 
B.83.3 N/m 
C.0.012 N/m 
D.98.8 N/m

anonymous · Answer

what about this one @JFraser

jfraser · Answer

the units of the spring constant are N/m, so what do you think you should do?

anonymous · Answer

1.2 x 100

jfraser · Answer

nope. look at the fraction in the unit i gave you

anonymous · Answer

but how do I get K alone

jfraser · Answer

you don't have to. "k" has units of N/m, so plug the units into the correct sides of the fraction and simplify

anonymous · Answer

I still don't understand @JFraser

jfraser · Answer

You've been given a force (100N) and a distance that the spring moved (1.2m). Combine them so that you get a spring constant that has units of N/m