Final answer:
The weight required to balance a block of 10N hanging 40cm from the midpoint of a meter rule by placing another block on the other side 25cm from the midpoint is indeed 16N, calculated using the principle of moments.
Step-by-step explanation:
The student asked to calculate the weight of the block that would balance a meter rule supported at its midpoint O, with a block of weight 10N suspended 40cm from O. To find the weight of the block at point A, 25 cm from O, we should apply the principle of moments, which states that for a system in equilibrium, the sum of the clockwise moments equals the sum of the anticlockwise moments around the pivot point.
Moment about O = Force × Distance
For clockwise moments (from the 10N weight):
10N × 40cm
For anticlockwise moments (let's call the weight at point A W):
W × 25cm
Setting the moments equal for balance:
10N × 40cm = W × 25cm
Therefore, W = (10N × 40cm) / 25cm = 16N.
So, the calculated weight is indeed 16N, which means the answer to the question is: a) Yes, 16N.