If a spacecraft in earth orbit is pushed by a thruster what will happen? a. the space craft will not move because it only works on earth. b. the spacecraft will change motion and will maintain this new orbit until the thruster is fired again. c. the spacecraft will move and then slowly come to a stop on its own. d. the spacecraft will not move due to air resistance.

For the orbital speed of a spacecraft we know that

here

M = mass of the planet around which satellite is revolving

r = orbital radius

Now when thruster is used by the spacecraft its speed will change due to which orbital speed will change.

Since here while changing the speed mass of the planet will be same

we can say the speed of the spacecraft will changed by thruster due to which its orbital radius will change

so the correct answer must be

b. the spacecraft will change motion and will maintain this new orbit until the thruster is fired again.

the only real purpose of sputnik 1 was to beat the us into space. we were getting close to launching a useful satellite, explorer 1 - which launched on january 31, 1958. the ussr had to beat that, so they launched sputnik 1 on october 4, 19