Physics: Gravitational Forces and Mass Variation

Questions and Answers

What is the new gravitational force exerted on one container by the other after varying the masses?

$F_0/2$

$F_0$

$2 F_0$

$3/4 F_0$ (correct)

What is the centripetal acceleration ab of satellite B in terms of a0?

a0/4

Which measuring devices are essential for finding the gravitational and inertial mass?

Meterstick and timer

Which experiment could be used to determine the gravitational mass of the object?

Experiment 1 only Signup and view all the answers

Is the student's claim about external forces acting on the planet supported by evidence?

Yes Signup and view all the answers

What procedure could be used to find the coefficient of static friction on a rotating disk?

Measure the distance from the center of the disk to the object's center of mass and record the time for one revolution. Signup and view all the answers

How does the gravitational force FY exerted by Planet Y compare to the gravitational force FX exerted by Planet X?

FY = 3/4 FX Signup and view all the answers

How does the gravitational field gX at the surface of Planet X compare with gY at the surface of Planet Y?

gx = 3gy Signup and view all the answers

Study Notes

Gravitational Forces and Mass Variation

Gravitational force between two containers of water changes with mass: when one container's mass increases to 1.5M and the other's decreases to 0.5M, the new gravitational force is 3/4 F0.

Centripetal Acceleration of Satellites

In centrifugal terms, if Satellite A orbits at distance d with acceleration a0, then a second satellite B at distance 2d has centripetal acceleration ab equal to a0/4.

Measuring Mass: Gravitational vs Inertial

To find gravitational mass, a string and spring scale are needed for a hanging object. For inertial mass, a spring scale is used to pull the object across a surface.
Essential measuring devices for both experiments include a meterstick and timer.

Experimental Methods for Mass Determination

Experiment 1 involves measuring an object's weight on an electronic balance and can determine gravitational mass.
Experiment 2 utilizes a spring scale for consistent force measurement while measuring speed, but it does not determine gravitational mass.

External Forces on Celestial Motion

The motion of a planet orbiting a star implies the only measurable external force is due to gravity from the star, albeit other external forces exist but have negligible magnitude.

Measuring Coefficient of Static Friction

To find the coefficient of static friction for an object on a rotating disk, measure the distance to the center of mass and increase the disk's rotation until the object slides off, timing one complete revolution.

Gravitational Forces on Satellites

Planet X (mass M, radius R) and Planet Y (mass 3M, radius 3R) have identical satellites at distance R above their surfaces. The gravitational force exerted by Planet Y (FY) is 3/4 the force exerted by Planet X (FX).

Gravitational Fields of Planets

At their surfaces, the gravitational field of Planet X (gX) is three times that of Planet Y (gY), formulated as gx = 3gy.

Description

This quiz explores key concepts related to gravitational forces, centripetal acceleration of satellites, and methods for measuring mass. It highlights the relationships between mass changes and gravitational force, as well as the techniques used in experiments to determine both gravitational and inertial mass.