Aptitude Test Problems in Physics Science for Everyone by S Krotov ( PDFDrive.com )

110 Aptitude Test Problems in Physics

while the second body moves towards it at a ve-

locity v 1 -I- v 2. Its acceleration is constant, equal

in magnitude to al + a 2 , and is directed against

the initial velocity. The condition that the bodies

meet indicates that the distance over which the

velocity of the second body vanishes must be long-

er than the separation between the bodies at the

beginning of motion; hence we obtain

1

max

(vi+ v2) 2

— 2 (aid- (JO •

1.6. Since the balls move along the vertical, we

direct the coordinate axis vertically upwards. We

plot the time dependence of the projections of the

velocities of the balls on this axis. Figures 122

and 123 show the dependences v 1 (t) and v 2 (t)

respectively (the moments of the beginning of mo-

tion are not matched so far). These graphs present

infinite sets of straight line segments with equal

slopes (since the acceleration is the same). These