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Physics question

Forthegood

He/Him
260
242
Can someone please help me with this I have to find the momentum of the moon orbiting the earth(idk if this makes sense) and the only values I have is the mass of the earth and the days it took for this to happen. And my thoughts were to convert days to hours and somehow find a way to convert that value to point where I can convert it to m/s so that I can calculate the momentum I am now stuck with the 1hours and idk what to do now💀💀please help.

Edit:

actually the mass of the moon was given and they are asking for the magnitude of the momentum
 
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Your expression seems quite vague. Mind showing the full question?

Otherwise, this is the best I can do:
This is an angular momentum question, which should be rather easy.

The moon takes a full month to make a full revolution around the Earth, so it'll take 2.6 million seconds.
30 days * (24 hours / 1 day) * (60 minutes / 1 hour) * (60 seconds / 1 minute) = 2.6e+6 seconds or 2.6 million seconds

The formula for angular momentum is L = m*v*r

L
is the magnitude of the momentum, m is the object's mass, and v is the tangential velocity (tangential velocity is calculated through the formula 2*π* r/T with T being time).


There's also this formula, which is more advanced: L = I*ω

I
is the moment of inertia (expressed as 0.4*M*R^2 for this case since the moon is a solid sphere) and ω is the angular velocity.

I'm unsure which formula will be used here since it depends on different levels and depends on what your teacher taught you. If you haven't learnt the moment of inertia and angular velocity method in class, then I suggest you're better off using the first formula.

I'm sure you should know the distance between the centre of the Earth and centre of the Moon, which is 384400 km which is 3.84e+8 m (384.4 million metres). You'll also need the radius of the moon which is 1.74e+6 m (1.74 million metres)

Calculate the tangential velocity: v = 2*πr/T = 2π*3.84e+8 / 2.6e+6 = 930 m/s

Now for the magnitude of momentum: L = m*v*r = 7.35e+22*930*1.74e+6 = 1.19e+32 kg*m^2/s
The second formula is pretty much an expanded version of the first formula, which is L = 0.4*M*R^2*ω and shortened to L = 0.4*M*R*v so simply times the first product by 0.4

Which will be: 1.19e+32*0.4 = 4.76e+31 kg*m^2/s
Anyway, I hope this helps. Physics type of crap will take in huge numbers, so the accuracy of the magnitude will be negligible. The main point you'll be tested on is that you'll be able to foil around and derive the algebraic formula, that'll be equivalent to the magnitude.
 
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