why is tht rockets need fuel in space?

Question

a rocket doesn't need fuel in space primarily because it doesn't need to do any work in space. we need fuel in earth because we have to do some work to overcome a lot of force like FRICTION,AIR RESISTANCE and gravitational force but in space there are none of theses factors and so if we accelerate once it then goes with a constant velocity. but if we could notice u might see tht rockets have fuels can u xplain whyyy?

Answer 1

Once a rocket is going it doesn't need any fuel, you are correct. However you need fuel for course corrections on the way. The tiniest error can put you off course by a huge amount over the weeks and months a rocket travels. So you need fuel to fire small rockets to adjust the course.

When you get to where you want to be you probably need to slow down so you need more fuel to do this.

Answer 2

Rockets need fuel to overcome gravity. There IS gravity in space, that is what keeps Earth orbiting the Sun instead of heading off into space in a straight line. If you just want to orbit wherever gravity would take you, no fuel is needed. But if you want to change your orbit to go someplace else, like the Moon or Mars or whatever, you need fuel.

Answer 3

If all you want is to keep traveling in a straight line at the same speed and never stop or change direction then you don't need any fuel in space once you achieve momentum theoretically.
There are gravitational forces passing any object in space that can and will modify your intended flight path.
If however you want to avoid a potential collision, land on the moon, return home, etc you need fuel to do it.
Assuming the fuel you are questioning is solely used for propulsion.

Answer 4

The law of uniform motion applies only if rocket is kick started in vacuum space to move in a straight line with uniform velocity. Rockets run along the shape of space ie a curve that needs constant change in the direction of space, a curved line and velocity is not uniform. Rockets also have to change the direction of motion by 180 degrees if they have to return to earth. They need fuel.

Answer 5

Fuel in a rocket is always used to accelerate (change speed - more or less) there are many reasons to do this in space. To rise to a higher orbit. To slow to orbit another body such as the moon or mars. Or to increase speed to leave the solar system completely. Though in practice many of these are done by aerobraking and gravity effects.

Answer 6

When a space craft is in orbit it is travelling at tens of thousands of kilometres per hour. Staying in orbit requires speed and trajectory to overcome Earths' gravity (space DOES have gravity. It looks like zero G because the spaceship and astronaut are 'falling' around the globe at the same speed).
Whenever a space craft wants to maneuver in space it needs to produce thrust and for that the space craft needs fuel.

Answer 7

Any vehicle requires energy to move whether it is on the ground or in the air(aeroplane) or a rocket in in the air or in space. The fuel after being burnt supply energy to the vehicle for motion according to 'Laws of Motion'. Thus , the fuel is always needed.

Answer 8

The only need to use fuel in space is when a change in velocity or direction is needed. If the course of the rocket is the desired one, then there's no need to fire it's engines.

Answer 9

If u are satisfied with your velocity then u are OK,but it may take a while. There is inertia so if u want to accelerate u must use fuel .

Answer 10

once they have reached terminal velocity in "Space" rockets arnt used. sometimes they are used to help turn etc.