A particle is in linear simple harmonic motion between two points, A and B, 10 cm apart. Take the direction from A to B as the positive direction and give the signs of velocity, acceleration and force on the particle when it is
at the end A,
Velocity: Zero; Acceleration: Positive; Force: Positive
at the end B,
Velocity: Zero; Acceleration: Negative; Force: Negative
at the mid-point of AB going towards A,
Velocity: Negative; Acceleration: Zero; Force: Zero
at 2 cm away from B going towards A,
Velocity: Negative; Acceleration: Negative; Force: Negative
at 3 cm away from A going towards B, and
Velocity: Positive; Acceleration: Positive; Force: Positive
at 4 cm away from B going towards A.
Velocity: Negative; Acceleration: Negative; Force: Negative
Explanation
In SHM, the equilibrium position is at the midpoint of AB. Taking A at -5 cm and B at +5 cm (with center at origin), the acceleration is given by a = -ω²x, always directed towards the center. Force has the same sign as acceleration. At extreme points (A and B), velocity is zero. The direction of velocity depends on whether the particle moves towards A (negative) or towards B (positive).