Does gravity effect how much energy is required to maintain speed on a moving object with a higher mass than another object?

[justamanwithsomequestions]

Assuming both objects are identical in size and shape, does gravity effect how much energy is required to maintain speed on a moving object with a higher mass than another object? 

[MigL]

Maintaining speed, in the absence of extraneous forces, requires no energy.

[exchemist]

5 hours ago, justamanwithsomequestions said:

Assuming both objects are identical in size and shape, does gravity effect how much energy is required to maintain speed on a moving object with a higher mass than another object? 

As @MigL says, no energy is needed, or at any rate no input of energy is needed. This is implied by Newton's First Law of Motion: https://www.oxfordreference.com/view/10.1093/oi/authority.20110803100232420

If, however, you are thinking about the specific scenario of periodic motion in a gravitational field, e.g. a planet orbiting the sun, or a pendulum in a clock, then gravity certainly affects how much kinetic energy the object will need to have, in order to follow a given trajectory. But again no input of energy is needed, once it has been initially set in motion.    

 

Edited July 25, 2022 by exchemist

[Danijel Gorupec]

hmm... I will try to be more careful...

Generally, yes.... you generally need to invest different amounts of energy to maintain speed of two objects of non-equal mass in gravitational field. The exception are the trajectories that are always perpendicular to the gravitational force.

[swansont]

8 hours ago, justamanwithsomequestions said:

Assuming both objects are identical in size and shape, does gravity effect how much energy is required to maintain speed on a moving object with a higher mass than another object? 

If it's a situation with friction, like an object sliding across a floor, the more massive object will have a larger frictional force; this is because the normal force would be equal to the weight, and the frictional force depends on the normal force. This will require a larger force to counteract friction to maintain constant speed.