A 1.5 kg test object moving at 2.4 m/s is brought to rest without rebound. The current design stops it in 0.01 s; a removable padded liner stops it in 0.03 s. Consider only the contact force along the horizontal direction and use average force = momentum change / stopping time. The proposed design offers a lower average stopping force for the camera, but adds bulk and may be difficult to recycle. Evaluate adoption for student reporters and the school's purchasing team, using both a force calculation and wider implications. Evidence limitation: A lower average force does not guarantee a lower peak force if the padding bottoms out.

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Momentum-change magnitude 3.6 kg m/s; average force falls from 360 N to 120 N. A conditional, tested adoption is defensible; average force alone does not establish complete safety or best value. The same test mass loses the same speed in both designs, so the impulse magnitude is 1.5 × 2.4 = 3.6 kg m/s. The longer stopping time changes the force, not the total required momentum change. The original average force is 3.6/0.01 = 360 N and the proposed force is 3.6/0.03 = 120 N. Both act opposite the initial motion. Relate the calculation to the specific benefit: a removable padded liner offers a lower average stopping force for the camera. The smaller average contact force is evidence for improved performance under this test, not a claim that energy or momentum disappears. Balance that benefit against a practical consequence: the design adds bulk and may be difficult to recycle. Include the needs of student reporters and the school's purchasing team, rather than allowing the cheapest purchase price or lowest force alone to decide. A justified recommendation is a monitored trial with a stated acceptance test before broad adoption. A lower average force does not guarantee a lower peak force if the padding bottoms out. Report peak force, durability and relevant access constraints alongside the average-force calculation.

A padded camera case

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