Example (8):
two spaceships (silver and black) are moving from the same starting point in the +
direction with constant accelerations. the silver spaceship has an initial velocity of vi
+2.00 km/s and an acceleration of +0.400 km/s2. the black spaceship has an initial >
velocity of +6.00 km/s and an acceleration of -0.400 km/s2.
oxf044
→ (a) find the time at which the silver spaceship just overtakes the black spaceship.
> (b) sketch graphs of v.(t) for the two spaceships.
(c) sketch a motion diagram showing the positions of the two spaceships at 1.0 s
interval.
(a) the position of either spaceships at later is given by:
x; =x, + 4x = x; + vix at+2, ata
when silver spaceship overtake the black, final positions are equal; thus
x; + visz at+4 at? = xin + vibx at+3at2
for both ships, the initial position was same (xis = x; thus it can be eliminated.