When a force of 3 Newton is exerted, the string reaches a new length. In the table, they did not state specifically how long the string became, therefore find the average to predict the new length made by using the 2 Newton and 4 Newton data on the table.
Step 1: ( 116+124 )/ 2 = 120mm
Remember, the question asks for the extension of the spring and not the total length. In the data given, at 0 Newton, the spring has a length of 108mm. To find the extension, subtract the new length with the original spring’s length to find out how much the string stretched.
Step 2: 120-108 = 12mm
Therefore, the answer is B. I hope this clarified for you.
ANSWER: B