Answered

Looking for reliable answers? Westonci.ca is the ultimate Q&A platform where experts share their knowledge on various topics. Connect with professionals on our platform to receive accurate answers to your questions quickly and efficiently. Get quick and reliable solutions to your questions from a community of experienced experts on our platform.


A spaceship of mass spaceship = 110000.0 kg starts at rest (vi= 0), then accelerates by releasing
exhaust gas of mass gas = 10600.0 kg with a velocity of gas = -100. What is the speed of the spaceship

Sagot :

Answer:

Approximately [tex]9.64\; {\rm m\cdot s^{-1}}[/tex] (assuming that the velocity of the exhaust is [tex](-100)\; {\rm m\cdot s^{-1}}[/tex].

Explanation:

When an object of mass [tex]m[/tex] travels at a velocity of [tex]v[/tex], the momentum [tex]p[/tex] of this object will be [tex]p = m\, v[/tex].

Assume that there is no external force on this spaceship. The total momentum of the ship and the exhaust will be conserved. In other words,

[tex]\begin{aligned}& (\text{Momenum of Spaceship, before}) \\ &+ (\text{Momentum of Exhaust, before}) \\ =\; & (\text{Momenum of Spaceship, after}) \\ &+ (\text{Momentum of Exhaust, after})\end{aligned}[/tex].

Rearrange to find the momentum of the spaceship after releasing the exhaust:

[tex]\begin{aligned} & (\text{Momenum of Spaceship, after}) \\ =\; & (\text{Momenum of Spaceship, before}) \\ &+ (\text{Momentum of Exhaust, before}) \\ &- (\text{Momentum of Exhaust, after})\end{aligned}[/tex].

It is given that the spaceship and the exhaust were initial stationary. Hence, initial momentum will be [tex]0\; {\rm kg \cdot m\cdot s^{-1}}[/tex] for both the ship and the exhaust.

[tex]\begin{aligned} & (\text{Momenum of Spaceship, after}) \\ =\; & (0\; {\rm kg \cdot m\cdot s^{-1}}) \\ &+ (0\; {\rm kg \cdot m\cdot s^{-1}}) \\ &- (\text{Momentum of Exhaust, after})\end{aligned}[/tex].

Since the exhaust is of mass [tex]10600\; {\rm kg}[/tex] and velocity [tex](-100)\; {\rm m\cdot s^{-1}}[/tex], the momentum of the exhaust after release  will be:

[tex]\begin{aligned} & (\text{Momenum of Exhaust, after}) \\ =\; & (\text{mass of Exhaust})\, (\text{Velocity of Exhaust, after}) \\ =\; & (10600.0\; {\rm kg})\, ((-100)\;{\rm m \cdot s^{-1}}) \\ =\; & (-1.06000\times 10^{6})\; {\rm kg \cdot m\cdot s^{-1}}\end{aligned}[/tex].

Divide the momentum of the spaceship by mass to find velocity:

[tex]\begin{aligned} & (\text{Velocity of Spaceship, after}) \\ =\; & \frac{(\text{Momentum of Spaceship})}{(\text{mass of Spaceship})} \\ =\; & \frac{((-1.06000\times 10^{6})\; {\rm kg \cdot m\cdot s^{-1}})}{(110000.0\; {\rm kg})} \\ \approx\; & 9.64\; {\rm m\cdot s^{-1}}\end{aligned}[/tex].