All Questions
Tagged with earth homework-and-exercises
74
questions
1
vote
1
answer
386
views
How can I obtain the position of the Earth on the orbit for given date?
I would like to be able calculate (or at least download some time-series data of) the position of the Earth on it's orbit at given date. For my purposes, it would be sufficient to account for the ...
CommunityBot
- 1
1
vote
2
answers
417
views
Proportional acceleration due to changing density of the Earth
My question has to to do with a recent video Minutephysics posted about the time it takes for a person to fall through the earth, found here
http://www.youtube.com/watch?v=urQCmMiHKQk
At around 4:05,...
CommunityBot
- 1
7
votes
1
answer
2k
views
How much negative charge do I accumulate by touching the earth?
The Earth carries a negative electric charge of roughly 500 thousand Coulombs (according to different sources I've seen). If I touch the Earth I should therefore pick up some of this electric charge (...
- 207k
1
vote
2
answers
2k
views
How to arrive to / calculate gravitational acceleration on Earth?
What are the exact steps and figures to calculate gravitational acceleration on Earth (9.8 m/s^2) and where do these figures come from?
(Please use an algebraic explanation, but assume understanding ...
0
votes
2
answers
5k
views
How small the Earth should be for it to become a black hole? [closed]
How small would the earth have to be squashed so that it would become a black hole?
- 1
1
vote
0
answers
22
views
Centre of Gravity of Earth-Moon Elevator [closed]
Suppose you have a cylindrical elevator that resembles a rod of mass $m$, cross-sectional area $A$ and uniform density $\rho$, with a length $L$ spanning the distance between the Earth and the Moon. ...
- 207k
0
votes
1
answer
53
views
At which colatitude $\theta$ is the error between $\vec g_{eff}$ and $\vec g$ maximum? [closed]
Suppose a plumb bob hangs without swinging, then the string defines the
effective direction of gravity. Suppose you are holding the bob on the surface of the
earth at colatitude $\theta$, where $\...
- 207k
0
votes
1
answer
45
views
Alfven waves in the ionosphere
I was given the following problem/question as a part of my homework in physics:
It is raining with thunder in Australia, and the lightnings generate transverse Alfven waves in the ionospheric plasma. ...
- 1,070
3
votes
2
answers
2k
views
What exactly will happen if a small planet collides with Earth?
This is a video of a simulation of Ceres (a dwarf planet) hitting Earth at 2000km/s.
What strikes me the most, is how fast the shockwave is moving. It takes about 6 minutes for the shockwave to pass ...
- 1,270
0
votes
2
answers
171
views
Would a body have any residual velocity if launched at escape velocity from the Earth's surface?
A body is lanuched at escape velocity from the Earth's surface i.e 11.2 km/s ,what would be it's velocity outside the Earth's gravitational field?
I guess it would be zero but there's another problem ...
- 2,547
2
votes
3
answers
3k
views
Can humans control rotation of the Earth?
I'm a class 12th student and this thought just struck me from nowhere.
Assume a situation where every human on this planet turns towards west. All of them start walking simultaneously in west ...
0
votes
0
answers
463
views
How much time dilation are we experiencing here on Earth? [duplicate]
We experience time dilation from speed and gravity, but we are in more than just the Earth's gravity field, but also the sun's and the galaxy's gravity field and we are both spinning at 1,670 km/h, ...
- 358k
0
votes
1
answer
127
views
Problem on Angle of declination [closed]
There was a problem in my book that read- A magnet is pointing towards geographic north at a place where the horizontal component of the Earth's magnetic field is 40 microtesla. Magnetic dipole ...
- 12.1k
0
votes
2
answers
375
views
Calculate Earth angular speed [closed]
How may I calculate Earth's angular speed at specific point (The green dot for example)?
Note: I know that angular speed $= \dfrac{2\pi}{T}$ But how may I found $T$ in this case?
I found too that $R_{\...
- 207k
-2
votes
1
answer
140
views
How high can you jump (at the corner) on Cube-Earth?
I have read this question:
Is the force of gravity always directed towards the center of mass?
And G. Smith's answer lists a site where they specifically talk about this case mathematically.
https:/...
- 29k