# Tangential speed and Earth

• avito009
In summary, the satellite has the correct tangential speed so that gravity only has the effect of changing the direction of travel, preventing it from getting close to the Sun or Earth.

#### avito009

Tangential speed is the linear speed of something moving along a circular path. So for a satellite the tangential speed of the satellite is just right so that gravity only has the effect of changing the direction of travel.

So now can we compare this satellite to the Earth? Since the Earth has some initial momentum - it is moving in a direction,which is perpendicular to the direction of the Sun from the Earth.

So that means both the satellite and the Earth have (Initial) momentum that prevents them from getting close to the Sun or Earth (In case of satellite).

You don't need the "initial" part. Any orbiting body possesses momentum.

avito009 said:
Tangential speed is the linear speed of something moving along a circular path. So for a satellite the tangential speed of the satellite is just right so that gravity only has the effect of changing the direction of travel.

In a perfectly circular orbit, yes. Objects in elliptical, parabolic, or hyperbolic orbits will not have a steady speed.

You are correct. Every object on Earth already has the velocity needed to orbit the Sun, whether it is on Earth or not. To put a satellite in orbit around the Earth, it is easier to launch it toward the East so that its velocity on the surface of the rotating Earth can help it reach the orbital velocity. The advantage is larger on the equator than in the U.S., and there is no advantage at the North Pole.

Ok so you mean that according to Newton's Second Law of Motion, the Force Law, the effect of a force on an object is to accelerate it in the direction of the force, according to the formula

F=m a

So the direction of the force of the Earth is towards the East as it rotates towards the East. Now if we were near the Equator we would move at 1000 mph speed. So a spacecraft launched from near the equator would need lesser fuel and would acquire the speed of 1000 mph. So since the direction of force is to the East and velocity is 1000 mph then the satellite also travels in the direction of this force.

## What is tangential speed?

Tangential speed, also known as tangential velocity, is the speed at which an object moves along its circular path. It is the component of velocity that is perpendicular to the radius of the circle at any given point.

## How is tangential speed related to Earth's rotation?

Earth's rotation causes objects on its surface to have a tangential speed. This speed varies depending on the latitude of the object, as objects closer to the equator have a larger tangential speed due to the larger circumference of the Earth at the equator compared to the poles.

## What is Earth's tangential speed at the equator?

At the equator, Earth's tangential speed is approximately 1670 kilometers per hour, or 1037 miles per hour. This is the fastest tangential speed on Earth.

## How does Earth's tangential speed affect gravity?

Earth's tangential speed plays a role in the strength of gravity on its surface. The faster an object's tangential speed, the more it will resist the force of gravity, resulting in a weaker gravitational pull on the object.

## Can tangential speed change?

Yes, tangential speed can change if the radius of the circular path changes. For example, if an object moves from the equator to the poles, its tangential speed will decrease due to the smaller circumference of the Earth at the poles. Additionally, changes in Earth's rotation speed can also affect tangential speed.