Calculating Local Gravity: How is g = 9.81m/s^2?

  • Thread starter Thread starter Kat007
  • Start date Start date
  • Tags Tags
    Gravity Local
AI Thread Summary
The local gravitational field, represented as g = 9.81 m/s², is calculated using Newton's law of universal gravitation, assuming Earth is a perfect sphere. The equation involves the gravitational constant (G), the mass of the Earth (M_E), and the radius of the Earth (R_E). By rearranging the formula G(M_E * m) / R_E² = mg, one can solve for g. The specific values for G, M_E, and R_E are essential for this calculation. Understanding these parameters is crucial for accurately determining the acceleration due to gravity at Earth's surface.
Kat007
28
0

Homework Statement


I am wondering how did the local graviational field (free fall acceleration) g = 9.81m/s^2 is calculated?


Homework Equations





The Attempt at a Solution



 
Physics news on Phys.org
It is usually calculated by assuming that the Earth is a perfect sphere and then by using Newton's law of universal gravitation to find the force on an object at the surface of the Earth. Input parameters are the gravitational constant and the radius and mass of the Earth.
 
So what is the actual equation used to obtain the g (with the values)?
Just out of general interest.
 
G\frac{M_E\:m}{R_E^2}=mg

Solve for g.
 
OK thank you for your time.
:)
 

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 'Minimum mass of a block'

Thread 'Minimum mass of a block'

Here we know that if block B is going to move up or just be at the verge of moving up will act downwards and maximum static friction will act downwards Now what im confused by is how will we know " how quickly" block B reaches its maximum static friction value without any numbers, the suggested solution says that when block A is at its maximum extension, then block B will start to move up but with a certain set of values couldn't block A reach...
View full post »
Thread 'Calculation of Tensile Forces in Piston-Type Water-Lifting Devices at Elevated Locations'

Thread 'Calculation of Tensile Forces in Piston-Type Water-Lifting Devices at Elevated Locations'

Figure 1 Overall Structure Diagram Figure 2: Top view of the piston when it is cylindrical A circular opening is created at a height of 5 meters above the water surface. Inside this opening is a sleeve-type piston with a cross-sectional area of 1 square meter. The piston is pulled to the right at a constant speed. The pulling force is（Figure 2）： F = ρshg = 1000 × 1 × 5 × 10 = 50,000 N. Figure 3: Modifying the structure to incorporate a fixed internal piston When I modify the piston...
View full post »

Similar threads

Motion on a rough inclined plane
Replies
5
Views
2K
Kinetic/Potential Energy - What am I doing wrong?
Replies
7
Views
1K
Lift and screw impact velocity
Replies
11
Views
1K
Calculate gravitational acceleration without mass of both objects
Replies
1
Views
2K
Calculating the frictional forces on a sliding box on a ramp
Replies
2
Views
3K
Calculating pressure within a system at a specific location?
Replies
8
Views
3K
Did I calculate the acceleration and Tension correctly?
Replies
9
Views
2K
What's the speed of the ball 1 second after it was kicked?
Replies
7
Views
3K
Calculating a ratio in Free Fall motion
Replies
7
Views
5K
Calculating G-Force on Gravitron Ride
Replies
1
Views
4K

Hot Threads

Recent Insights

Back
Top