As from the title, I am trying to find for Venus, Earth, and Neptune:(adsbygoogle = window.adsbygoogle || []).push({});

a) the orbital angular displacement in one day in radians

b) the centripetal acceleration

c) the centripetal force

Relevant Equations:

Centrip accel: ac=v^2/r=4pie^2/T^2

Centrip force: Fc=ma=mv^2/r=4pie^2mr/T^2

related equations

Spin speed at equator: (2pie/T)*r=wr

ang. speed: w=change in theta/ change in time

orbital per: T=2pie*r/v

I know:

length of day in earth days--and in seconds

radius of planet in meters

length of year in earth days--and in seconds

Radius of orbit around sun in meters

My attempt at find centrip accel

Earth: in process

Venus: in process

Neptune: length of year in secs=(2pie*rad of orbit around sun in meters)v

=v=(2pierad of orbit around sun in meters)/length of a year in secs

=31466412=(2pie1.49E11m)v

=297371. m/s

a=v^2/r

a=(29737.1 m/s^2)/1.49E11m=1.99E-7 rad/s

I used the same method for finding the other planets but didn't write them in order to check whether or not it was right.

My attempt at find centrip force:

...yeah I don't even know where to begin....

mv^2/r so......mass (of earth of a person of what???) * velocity of earth^2/radius of planet..? It seems so easy...but is it? inputting for mass of earth I get (1024 kg)((3.5E4m/s)^2)/6378000m=.001967x10^8

as for orbital angular displacement in one day...I'm lost...

So why didn't I just learn this in physics class? Because I was sick on the days my class started learning rotational mechanics--am STILL sick--and have been trying to teach myself by looking at online sources and videos. But this homework was assigned (I know because my friend sent it to me a few mins ago)....now he isn't online and I don't really have anyone else to go to help for...plus he's one of those "learn by sweat and tears" kind of people--in other words, not a very good one (or a very good one depending on how you look at it)...so even if he was online I don't think he would be much help....I just can't learn easily from that kind of "help".....However...though giving me the answers might seem like a bad way to teach me I am in fact VERY good at working backwards and understanding, so if someone was to give step by step instructions on how to solve the above questions (imputing the known variables I listed in word form), then I know I could understand the relationship better.

Anyhow...can anyone help me? I would GREATLY appreciate help as right now I am on the verge of tearing my hair out...OK not true...but I've been blowing my nose for hours and I feel extremely dizzy and I HAVE to go to school tomorrow so.....

I digress......way too much...sorry :(

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# Homework Help: Orbital angular disp. in 1 day & centrip. force and Acceleration of planets help!

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