PEQ Two particles A and B, move with constant velocities v1 and v2 respectively. At the initial moment, their position vectors are r1 and r2 respectively. The condition for particles A and B for their collision will be 1. r 1 − r 2 | r 1 − r 2 | = v 2 − v 1 | v 2 − v 1 | r1-r2r1-r2=v2-v1v2-v1 2. r 1 ⋅ v 1 = r 2 ⋅ v 2 r1·v1=r2·v2 3. r 1 × v 1 = r 2 × v 2 r1×v1=r2×v2 4. r 1 − r 2 = v 1 − v 2 r1-r2=v1-v2 Ruhul Amin Alig
PPYQ A particle shows the distance-time curve as given in this figure. The maximum instantaneous velocity of the particle is around the point: Ruhul Amin Alig
PEQ Spherical wavefronts, emanating from a point source, Strike a plane reflecting surface. What will happen to these wave fronts, immediately after reflection ? A They will remain spherical with the same curvature, both in magnitude and sign. B They will become plane wave fronts. C They will remain spherical, with the same curvature, but sign of curvature reversed. D They will remain spherical, but with different curvature, both in magnitude and sign. Ruhul Amin Alig
