"The Law of Universal Gravity" Gravity and Space Navigation PPT Courseware

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"The Law of Universal Gravity" Gravity and Space Navigation PPT Courseware

Part 1: Essential knowledge and foundation of literacy

1. Gravity between planets and the sun

[Thinking] On the basis of previous research, Newton believed that changing the speed in any way requires force. Which celestial body exerts the force on a planet to move it?

Tip: sun

1. The gravity of the sun on the planet: The gravity F of the sun on the planet is directly proportional to the mass m of the planet, and inversely proportional to the square of the distance between the planet and the sun (r2), that is, F∝____.

2. Gravity of planets and sun:

(1) Size: The gravitational force between the planet and the sun is directly proportional to the mass m of the sun, that is, F∝. The equation written is F=________.

(2) Direction:_____________.

(3) Proportional coefficient G:

Numerical explanations about G that are consistent with scientific reality include _______.

①It has nothing to do with the mass of the sun.

②Related to the mass of the sun.

③It has nothing to do with the mass of the planet.

④Related to the mass of the planet.

⑤It has nothing to do with the distance from the sun to the planet.

⑥Related to the distance from the sun to the planets.

2. Monthly-ground inspection

[Thinking] Does the force that pulls the moon and causes it to move around the earth follow the same laws as the force that pulls the apple down and the force of the sun on the planets?

Tip: Follow the same rules

1. Conjecture: The force that keeps the moon moving around the earth and the force that makes the apple fall are the same force, and they also follow the law of "__________".

2. Inspection method:

(1) The acceleration of an object moving in the lunar orbit: a=______.

(2) The acceleration of the moon’s uniform circular motion around the earth: a=_______.

(3) Comparison results: The acceleration of the moon at the orbital height is approximately equal to _______________.

3. Conclusion: Ground objects are subject to the gravity of the earth, the moon is subject to the gravity of the earth, and the gravity of the sun and planets follow the same laws.

3. The law of universal gravitation

[Thinking] Since the attraction between the sun and the planets, between the earth and the moon, and between the earth and ground objects is "proportional to the mass of the two objects and inversely proportional to the square of the distance between them", is it Is there such a force between any two objects?

Tip:Yes

1. Content: Any two objects in nature _________, the direction of gravity is _____________, the size of gravity is _____ multiplied by the mass m1 and m2 of the object, and is _ with the square of the distance r between them. ____.

2. Formula: F=_______.

4. Gravitational constant

1. Measurer: _________.

2. Value: G= ____________________.

The Law of Universal Gravitation PPT, Part 2: Key Abilities and Literacy Formation

1. The law of universal gravitation

1. Characteristics of the law of universal gravitation:

(1) Universality: Universal gravitation exists between any objects with mass in the universe (between celestial bodies, between terrestrial objects, and between microscopic particles).

(2) Reciprocity: The gravitational force of the interaction between two objects is a pair of action force and reaction force, which is consistent with the interaction of forces.

(3) Macroscopic nature: The universal gravitation between celestial bodies is relatively large, and it is the reason that governs the motion of celestial bodies. The gravitational force between ground objects and microscopic particles is so small that it is not enough to affect the movement of objects, so it is often ignored.

(4) Particularity: The gravitational force between two objects is only related to their own mass and the distance between them, and has nothing to do with the nature of the space in which they are located.

2. Conditions for the application of the law of universal gravitation:

(1) The formula of the law of universal gravitation is applicable to the calculation of the gravitational force between particles.

(2) For the interaction between actual objects, it is also applicable when the distance between the two objects is much larger than the size of the object itself (the object can be regarded as a particle).

(3) The magnitude of the gravitational force between two spheres with uniform mass distribution can be solved by the formula of the law of universal gravitation. r in the formula is the distance between the centers of the two spheres.

(4) The gravitational force between a sphere with uniform mass distribution and a particle outside the sphere can also be solved by the formula of the law of universal gravitation. r in the formula is the distance between the particle and the center of the sphere.

[Typical example demonstration]

To reduce the gravitational force between two objects to its original value, the following methods cannot be used: ()

A. Reduce the mass of the two objects by half and keep the distance unchanged.

B. Reduce the distance between the two objects and the mass of the two objects to their original values.

C. Double the distance between the two objects and keep the mass unchanged

D. Reduce the mass of one of the objects to its original value and keep the distance unchanged

【Literacy Training】

1. (Multiple choices) Regarding the expression F=G of the universal gravitation between two objects with masses m1 and m2, which of the following statements is correct ()

A. The G in the formula is the gravitational constant, which is derived from experiments rather than artificially defined.

B. When the distance r between two objects tends to zero, the universal gravitation tends to infinity

C. The magnitude of the gravitational force exerted by m1 and m2 is always equal.

D. The gravitational force between two objects is always equal in magnitude and opposite in direction. It is a pair of balancing forces.

[Analysis] Choose A or C. The gravitational constant G was first measured by the British physicist Cavendish using an ingenious "precision" torsion balance experiment, so option A is correct; the universal gravitation between two objects is a pair of action and reaction forces , they are always equal in size and opposite in direction, acting on two objects respectively, so option C is correct and D is incorrect; the formula F=G is applicable to the interaction between two particles. When the two objects are very close to each other, the two objects cannot It is regarded as a particle, so option B is wrong.

2. The distance between two spheres of uniform mass is r, and the gravitational force between them is 1×10-8 N. If their mass and distance are increased to twice the original value, the gravitational force between them is ()

A.1×10-8 NB.2×10-8 N

C.4×10-8 ND.8×10-8 N

[Analysis] Choose A. According to the law of universal gravitation F=G, if their mass and distance are increased to twice the original value, then the universal gravitation will not change and is still 1×10-8 N, so option A is correct.

[Typical Example 1] As shown in the figure, P and Q are two particles with the same mass, placed at different latitudes on the surface of the earth. If the earth is regarded as a uniform sphere, the two particles P and Q rotate at a constant speed with the rotation of the earth. Circular motion, then the following statement is correct ()

The centripetal forces of A.P and Q in circular motion are equal in magnitude.

The gravity of the earth on B.P and Q are equal.

The linear velocities of C.P and Q in circular motion are equal.

The gravity of the earth on D.P is greater than the gravity of the earth on Q

Keywords: PPT courseware for high school physics compulsory course 2 from the People's Education Press is available for free download, Law of Gravity PPT download, Gravity and Space Navigation PPT download, .PPT format;

For more information about the "Universal Gravity and Space Navigation Law of Universal Gravity" PPT courseware, please click on the Universal Gravity and Space Navigation PPT Law of Universal Gravity PPT tag.

"The Law of Universal Gravity" Gravity and Space Navigation PPT quality courseware:

"Law of Universal Gravity" Gravity and Space Navigation PPT High-quality Courseware Part One: Core Competency Objectives Physical Concepts Understand the existence of gravity between the sun and planets, and master the content and expression of the law of universal gravitation. Scientific thinking According to Kepler's planetary movements...

"The Law of Universal Gravity" Excellent courseware of Universal Gravity and Space Navigation PPT:

"The Law of Universal Gravity" Excellent Gravity and Space Navigation PPT Courseware Part One Content: Learning Objectives 1. Know that the sun's gravity on the planet provides the centripetal force for the planet to move in a circular motion, and be able to use Kepler's third law and Newton's law of motion to deduce that the sun and OK..

"The Law of Universal Gravity" Universal Gravity and Space Navigation PPT:

"Law of Universal Gravity" Universal Gravity and Space Navigation PPT Part One Content: Learning objectives (1) Understand the existence of gravitational force between the sun and planets; (2) Be able to deduce the gravitational force between the sun and planets based on Kepler's law of planetary motion and Newton's third law Gravity expression; (3)..

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Update Time: 2024-11-14

This template belongs to Physics courseware People's Education Press High School Physics Compulsory Course II industry PPT template

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