Calculate the gravitational field strength

AI Thread Summary
To calculate the gravitational field strength of the moon, the formula g = F/m is used, where F is derived from Newton's law of universal gravitation. The gravitational force F is calculated using F = GmM/r^2, with G being the gravitational constant, m the moon's mass, and r its radius. The discussion clarifies that the mass of the object experiencing the gravitational field (M) cancels out, simplifying the calculation. The correct approach confirms that the mass does not need to be included in the final formula for gravitational field strength. The key takeaway is that the gravitational field strength can be determined without needing the mass of the object being affected.
sweet877
Messages
30
Reaction score
0
From the radius (1740 km) and mass (7.36 X 10^22 kg) of the moon, calculate gravitational field strength for this body.

g = F/m = F/(7.36X10^22 kg)
F = GmM/r^2 = (6.67X10^-11)(7.36X10^22)M/(1740X10^3)^2
What is the big M?
 
Physics news on Phys.org
do you need it?
 
I would think not...but why? Did I use the wrong formula to find F?
 
Ah I got it.
mg = GmM/r^2, the small ms cancel out. Thanks!
 

Thread 'Errors and significant figures'

I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
View full post »
Thread 'Collision of a bullet on a rod-string system: query'

Thread 'Collision of a bullet on a rod-string system: query'

In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
View full post »
Thread 'A cylinder connected to a hanging mass'

Thread 'A cylinder connected to a hanging mass'

Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
View full post »

Similar threads

Find the gravitational field strength of planet X
Replies
10
Views
2K
Gravitational Field Strength at the equator and poles
Replies
23
Views
3K
Gravitational Field Multiple Choice Help
Replies
5
Views
2K
Gravitational field strength at a point
Replies
9
Views
4K
Calculating the Distance of a Zero Gravitational Field Between Earth and Moon
Replies
2
Views
2K
Gravitational field strength of a mass
Replies
17
Views
2K
Gravitational field strength problem- help needed
Replies
1
Views
3K
Calculate gravitational field strength above surface of Mars
Replies
6
Views
16K
How Does Apparent Weight Change for an Astronaut Near the Moon?
Replies
5
Views
3K
Gravitational field strength of 0
Replies
1
Views
2K

Hot Threads

Recent Insights

Back
Top