Question

If a rubber band is stretched a particular distance,

the restoring force is defined as the force needed to
restore the rubber band to its original form. When a
particular rubber band is stretched to a length of 30
centimeters, the restoring force is –35 newtons, and
when it is stretched to a length of 90 centimeters, the
restoring force is –125 newtons. For every additional
20 centimeters from its original form, the restoring
force decreases by c newtons, where c is a constant.
What is the value of c ?

Answer 1

c = -30 N

Step-by-step explanation:

Initial length L1 = 30 cm

Initial restoring force F1 = -35 N

Final length L1 = 90 cm

Final restoring force F2 = -125 N

Between 30 cm and 90 cm, one will increase extension by 20 cm 3 times. This means the force between -35 N to -125 N increased by 3 constant value.

-125 - (-35) = -90 N.

this means that the constant is,

c = -90/3 = -30 N

This means that for every 20 cm increase, there is a 30 N decrease in the restoring force