A monkey of mass $30$ kg climbs a vertical rope hanging from the ceiling with an upward acceleration of $2$ m/s². Find the tension in the rope. (Take $g = 10$ m/s².)
A$300$ N
B$360$ N
C$420$ N
D$480$ N
Answer & Solution
Correct answer: B. $360$ N
**Free-body diagram of the monkey.** Tension $T$ acts upward; weight $mg$ acts downward.
**Newton's second law (upward positive).** $T - mg = ma \Rightarrow T = m(g + a) = 30 \times 12 = 360$ N.
**Distractor check.** Option A ($300$ N) is the static value $mg$ — what the rope would feel if the monkey were stationary. Option C ($420$ N) substitutes $a = 4$ by mistake.
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