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0 votes
3 answers
81 views

Pseudo Orbital motion only due to Coriolis force

Planet, say of mass M and radius R is rotating with some angular velocity ω and a object of mass m (initially on the surface and rotating with the planet) was launched with velocity v vertically ...
0 votes
0 answers
36 views

With what vel. would you have to launch an object vertically up from the earth's surface for it to land back again at it's initial launching point?

[Can skip reading this part] First of all, Newtonian gravity shall be considered whilst trying to solve this question. It's been on my mind for a long, long time and has been bothering me since. I ...
1 vote
3 answers
9k views

What exactly will happen if you jump in the upward direction from a roof of on a moving car?

I'm not a physicist and I'm a little bit puzzled with the image below: I know it's a joke but if we assume we don't have air resistance what exactly will happen if someone jump in the upward ...
1 vote
4 answers
94 views

A problem Understanding how a two-body system of planets starts rotating around barycentre

Consider,We are Creating a Two-body system in free space,Where no other mass exists,Let's Take First Mass M1 and hold it,Now bring Second Mass M2,hold it up,Now we are giving a suddenly impulse To M1 ...
1 vote
3 answers
4k views

Relative speed of Geostationary satellite with respect to Earth?

I was wondering whether relative speed of geostationary satellite with respect to earth is zero or not. Since angular velocity of satellite about earth is same as angular speed of earth about its own ...
6 votes
2 answers
680 views

How does the orbital motion of reduced mass tell us how the individual planets/stars move?

To give context to my question, here is Kepler's first Law restated in terms of reduced mass. Here, $\vec{r}$ is the position vector of the reduced mass whose origin lies at the centre of mass of the ...
2 votes
1 answer
190 views

Relative speed of satellites in different orbits [closed]

The question is "The Hubble Space Telescope is in orbit around the Earth at a height of 560km above the Earth’s surface. Take the radius and mass of the Earth to be 6.4×10^ 6m and 6.0×10^24 kg, ...
2 votes
3 answers
13k views

Dropping a ball in a fast moving train

If I drop a ball in a train moving at a constant speed, will it land on the spot I aimed it at or a little away as the train has moved while it was in air? If it lands away, will the observer not know ...
0 votes
1 answer
49 views

Rotation Vs hovering

Say, a person with a jetpack is in the moon. If the person is balanced over his weight by an upward force generated by the jetpack above the surface of the moon (kind of hovering for some time and at ...
3 votes
3 answers
298 views

How to conceptualize Newton's apple?

I have no physics background, which is the genesis of my question. In pop-science, it is frequently mentioned that Newton's apple didn't fall toward his head, but rather that his head came up and ...
0 votes
1 answer
140 views

Can we move without moving? [duplicate]

So here is the question, If I jump and hover over the ground for sometime why don't we move away from the point I jumped from? Because earth is rotating so if I hover long enough we should move from ...
0 votes
1 answer
122 views

Gravity on hovering objects

Imagine a remote controlled toy helicopter vertically takes off from a table and hovers at about one metre over the table that is of one metre height: hence, the total altitude is 2 metres. What will ...
0 votes
2 answers
451 views

Earth's rotation and a helicopter [duplicate]

Imagine a helicopter that took off from point A on the ground and goes vertically in the air to a certain fixed point B in the atmospheric area at a certain fixed altitude with enough fuel to stay ...
6 votes
1 answer
806 views

Shouldn't the escape velocity of earth (with respect to earth) be less than $\sqrt{\frac{2GM}{R}}=11.2\,\mathrm{km/s}$

We know that the escape velocity of earth is, $$\sqrt{\frac{2GM}{R}}=11.2\,\mathrm{km/s}$$ Where $G=6.67×10^-11$ $M=\text{mass of earth}$ $R=\text{radius of earth}$ So if throw a object ...
0 votes
4 answers
3k views

What is the work done by individual forces on an object at rest?

An object at rest is being acted on by several forces which add up to zero. For instance, a box is sitting on an inclined plane. It is not falling down the plan because the force of friction cancels ...

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