Universal Gravitation Practice

AI Thread Summary
The discussion focuses on calculating the gravitational force exerted by Earth on an 80.0-kg astronaut at an altitude of 2.5 times Earth's radius. The formula used is FG = (Gm1m2) / r², where G is the gravitational constant, m1 is the mass of Earth, and m2 is the mass of the astronaut. The user initially calculated FG as 2.00x10^12 N but later confirmed the correct force is 64 N. Clarification on the variables indicates that altitude refers to the height above Earth's surface, while r represents the distance from Earth's center. Understanding these definitions is crucial for accurate gravitational force calculations.
chroncile
Messages
34
Reaction score
0

Homework Statement


What force does Earth exert on a 80.0-kg astronaut at an altitude equivalent to 2.5 times Earth's radius?


Homework Equations


FG = (Gm1m2) / r2
Radius of Earth: 6370 km
Mass of Earth: 5.97x1024 kg

The Attempt at a Solution


FG = (Gm1m2) / r2
FG = (G x MEarth x 80 kg) / (6370 x 2.5)2
FG = 2.00x1012 N

The correct answer is 64 N
 
Physics news on Phys.org
What is G? And altitude means "above the surface of the Earth" and r means the distance from the centre of Earth.

ehild
 

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 '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

Determine the mass of the planet using Newton’s Law of Universal Gravitation
Replies
2
Views
3K
Calculating the Length of a Space Elevator Rope
Replies
18
Views
2K
Ratio of the Magnitude of gravitational force?
Replies
5
Views
5K
A 12 kg meteor experiences an acceleration of 7.2 m/s^2....
Replies
7
Views
3K
How High Is a Meteor When It Accelerates Toward Earth?
Replies
4
Views
3K
Weight difference at Mt. Everest summit vs. sea level
Replies
2
Views
1K
Universal Gravitation and Gravitational Field Question
Replies
6
Views
13K
How Does Distance from Earth Affect Spacecraft Weight?
Replies
4
Views
3K
Universal Gravitation problem, help with final statement.
Replies
18
Views
2K
Universal Law of Gravitation problem
Replies
1
Views
2K

Hot Threads

Recent Insights

Back
Top