How can rockets escape from gravity?

Answer 1

Escape velocity is defined to be the minimum velocity an object must have in order to escape the gravitational field of the earth, that is, escape the earth without ever falling back.

From the surface of the Earth, escape velocity (ignoring air friction) is about 7 miles per second, (11.2 km/sec) or about 25,000 miles per hour. Given that initial speed, an object needs no additional force applied to completely escape Earth's gravity.

More can be seen about this in the related link below.

Answer 2

Rockets can escape Earth's gravity by achieving enough velocity to overcome the force of gravity. This is done by propelling the rocket with enough thrust to reach a speed called the escape velocity, which varies depending on the mass of the planet and the height of the rocket above its surface. Once the rocket reaches escape velocity, it can break free from the gravitational pull and travel into space.

Answer 3

Escape velocity is the velocity needed to escape the gravitational pull of a body. The escape velocity of the Earth is about 7 miles per second. The escape velocity of the Sun is about 25 miles per second.

Answer 4

The ev of the Moon is 2.38 km/s compared to the Earths 11.186 km/s
2.4 km (1.5 miles) per second.

Compare with 11.2 km (7.0 miles) per second from earth.
Escape velocity from the Moon is: 2.38 km/s Escape velocity from the Earth (to get to the Moon) is: 11.2 km/s

Answer 5

As we throw a stone vertically up it will go to certain height and fall back towards the earth. This is because the kinetic energy given to the stone gets changed into gravitational potential energy as it moves away from the centre of the earth. As the given energy is not enough to escape it falls back. So if we provide a velocity such that its PE becomes zero as it moves away from the surface then the stone will never come back. It will be out of the gravitational pull of the earth. Such a minimum velocity provided on the surface vertically upward so as to escape from the pull is defined as escape velocity. We can derive the same as Ve = ./ 2gR. Here g is the acceleration due to gravity and R is mean radius of the earth. If we calculate it will be 11.2 km/s. So if we throw a stone with this speed vertically up it will certainly escape.

But in case of rockets it is not advisable to send it at this speed. Because with this speed due to the friction with the air, enormous heat will be produced and the rocket will get burnt totally. Practically there will be multistage of rockets. First one will give the necessary lift to a certain height and the second would give the next push by increasing the speed and third if so would give the needed speed at that height so as to escape and go in a desired direction.

Answer 6

If you imagine a spaceship from your favorite cartoon, you can watch it take off into the sky but the rocket needs to be moving very fast. This is because the rocket needs to reach escape velocity or the velocity is takes to get away from a gravitational field. The speed needed to escape Earth is about 11.2 km/s (that's kilometers per second).

Answer 7

It's a sort of limiting speed. If you throw anything up from Earth at a speed of less than 11.2 km/sec, it will fall back to Earth. If you throw it up at a greater speed, it will escape (hence the name) from Earth, and not come back.

Answer 8

The escape velocity is different for different planets, stars, or other objects. In the case of planet Earth, the escape velocity is 11.2 km/sec.

Answer 9

A rocket needs to travel at 25 000 mph to reach low-earth orbit.

Answer 10

the rocket's thrusters, or "rockets" have more force than the force of gravity allowing them to escape the force of gravity