Physics - Circular Motion Question with Solution | TestHub
A bob is attached to a string as shown in the figure. At the lowest point it is given a horizontal velocity u. For different values of u, it can have different total acceleration at different points. For each of the points marked in column-I, match the possible direction(s) of total acceleration.
List - I | List - II |
(A) Point A | (P) ← |
(B) Point B | (Q) ↑ |
(C) Point C | (R) ↓ |
(D) Point D | (S) ↙ |
| (T) ↖ |
Options:
Answer:
Solution:
Total acceleration = vector sum of centripetal acceleration (towards the centre) and tangential acceleration (component of g along the tangent).
At A (lowest point), tangential component is zero; acceleration is purely centripetal, directed upward → Q.
At B, centripetal part points left and tangential part downward; depending on u the sum can point left, down-left or up-left → P, S, T.
At C and D the possible directions of the sum are ↓ and ↙ → R, S.
Answer: (A) A → Q, B → PST, C → RS, D → RS
