Q59 · Practice questionComplex familiar4 marks
QUESTION 59 (4 marks)
A launcher fires identical projectiles at the same speed. The measured ranges are:
| angle (°) | 20 | 30 | 40 | 50 | 60 | 70 |
|---|---|---|---|---|---|---|
| range (m) | 31.6 | 40.9 | 46.4 | 46.1 | 41.2 | 31.4 |
Analyse the data to identify two patterns and predict the launch angle that would produce the maximum range.
WORKED SOLUTION
4 marksPractice marking scheme
ANSWER
Complementary angles give similar ranges; the range rises toward and then falls. Maximum range is predicted at about .
Worked solution
The pairs , and have approximately equal ranges. These are complementary angles, consistent with . The range increases as the angle approaches the mid-40s and decreases after it. Therefore the maximum is predicted near . Small mismatches between complementary pairs are consistent with experimental uncertainty.
Identifies the complementary-angle pattern.
Identifies increase then decrease in range.
Predicts approximately 45 degrees.
Links conclusion to data or projectile relationship.
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