Question

A spacecraft flying in a straight course at 72 km/s fires its rocket motors for 6.0 seconds. At the end of 6.0 seconds its speed becomes 120 km/s in the same direction. The spacecraft's average acceleration while the motors were firing is 8 km/s2 10 km/s2 17.5 km/s2 19 km/s2

Answer 1

Answer:

u=Initial Velocity =72Km/sec

Time=t=6sec

V=Final Velocity =120Km/sec

Average Acceleration

$= \frac{v - u}{t}$

$= \frac{120 - 72}{6} = \frac{48}{6}$

$= 8$

So The spacecraft's average acceleration while the motors were firing is 8 km/s2 .

Option A