Final answer:
To measure the proportionality constant k of a rubber band, you can use Hooke's Law and rearrange it to solve for k. If two similar bands are attached to the same mass, the total stretch can be calculated by adding the individual stretches either in parallel or in series.
Step-by-step explanation:
To measure the proportionality constant k of a rubber band, you can use Hooke's Law, which states that the force applied to a spring-like object is directly proportional to the amount it stretches or compresses. In this case, the rubber band is acting like a spring. To find the constant k, you can rearrange Hooke's Law to solve for it: k = F/x, where F is the force applied and x is the amount the rubber band stretches. By measuring the force applied and the corresponding stretch, you can calculate k. If two similar rubber bands are attached to the same mass, the total stretch can be calculated by adding the individual stretches. If the rubber bands are attached in parallel, meaning both ends are connected to the mass separately, the total stretch would be double the individual stretch. If the bands are attached in series, meaning one end of each band is connected to the mass while the other ends are tied together, the total stretch would be the same as the individual stretch.