What would happen if Two tat astronauts each of mass 120 kg are travelling in a closed spaceship moving at a speed of 15 km/s in the outer space far removed from all other materials objects. The total mass of the spaceship and its contents including the astronauts is 660 kg. If the astronauts do slimming exercise and thereby reduce their mass to 90 kg each , with what velocity will the spaceship move?

Note by Jai Gupta
5 years, 1 month ago

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15 km/s as it's momentum will change due to external forces and not by forces coz of slimming. Moreover the total mass of the spaceship is still the same, as the lost mass is converted in the form of sweat but is still in the spaceship...

- 5 years, 1 month ago

- 5 years, 1 month ago

No change in the answer....Enlighten ME!!

- 5 years, 1 month ago

Kk then It will move with the same velocity. Why this question is asked by me because in this the total mass will remain same because spaceship is isolated means it is isolated from surrounding. Whatever mass which will be change remains in the spaceship

- 5 years, 1 month ago

I wrote that in the last line if you can please read it again. It is clearly stated that the total mass of the spaceship remains conserved. Don't complain without reading carefully. And moreover, only your reason is not correct. My first line, that the total external force is zero is also a right reason!!

- 5 years, 1 month ago

kkk and dont lie you edit it

- 5 years, 1 month ago

Lol!!! Hahaha...i dont believe it...the comment says last modified 4 days ago, and you posted the prob 4 days ago...that means i wrte my answer only once...hehe

- 5 years, 1 month ago

Kk Don't fight yaar You are correct and I am wrong k

- 5 years, 1 month ago