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I have been thinking on the effect of the centrifugal/centripetal forces from the orbital movement of the earth around the sun, which might perhaps affect the gravity.
In nighttime we are on the outside of the orbital path and in daytime we are on the inside, facing the sun. We would then, to my belief, in daytime be "pushed harder" to the ground, and in nighttime this force would be in the opposite direction from the ground.

Using the formula for determining the centrifugal force I have come to the conclusion that for a normal human it should be in the order of 0.5 Newton

Is this thinking correct or have I missed something important? If correct, is this difference in gravity measurable or deteminable?

Qmechanic
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Beta
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    Your thinking isn't quite correct, since you're almost in freefall around the Sun (it's not exact because your position is displaced slightly from the proper orbital distance due to the Earth being in the way), but there are tidal effects from the Moon and the Sun. There are some great articles, with graphs, at leapsecond.com. – PM 2Ring Dec 22 '18 at 20:40
  • thanks for the link to these articles @PM2Ring It was indded a precision pendulum clock tha t made me wonder about this effect. – Beta Dec 22 '18 at 20:51
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    Related: https://physics.stackexchange.com/q/121775/2451 and links therein. – Qmechanic Dec 22 '18 at 22:06
  • Ignoring the Moon, you would be heaviest at sunrise and sunset rather than at noon and midnight, which would be when you're lightest. The Moon's tidal effect however is twice that of the Sun, so you can't ignore the Moon. – David Hammen Dec 23 '18 at 00:24

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Centripetal forces do not affect gravitational forces. All the forces add to a net force.

Given the Earth's orbital motion around the sun, the effective force you would feel towards the center of the Earth is indeed smaller (assuming you're not standing on the top of the Earth).

There is also an effect on the apparent gravity by Earth's own rotation.

psitae
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