"Newton's First Law" PPT

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"Newton's First Law" PPT

Part One: Thinking:

1. Is the change in the motion state of an object necessarily due to the action of force?

2. What will happen if a force is exerted on an object in a certain state of motion?

3. What will the object do when there is no force acting on it?

Please guess:

1. What will happen to the book that is still in the teacher's hand if there is no force?

2. What will happen to the roller coaster that is moving in a curve in the picture if all external forces suddenly disappear?

Newton's first law PPT, part 2 content: exploration

The effect of resistance on the motion of an object

1. What is the object of experimental research?

2. How to change the size of resistance?

3. What does it mean to see how fast the car speed decreases?

4. In order to compare the distance the car continues to move on the horizontal plane of different materials, what factors need to be controlled?

5. If you are given an inclined plane, how do you ensure that the car has the same initial speed on the horizontal plane of different materials?

Establish a hypothesis: The greater the resistance, the faster the speed of the car decreases.

Design an experiment: In this experiment, what conditions will be controlled to remain constant? What method is used to control it?

Control the speed and direction of the car when it enters the horizontal plane to remain unchanged: the same car slides down from the same height on the same slope.

What conditions need to change in this experiment? What method is used to control it?

The amount of resistance the car receives on the horizontal surface: spread objects with different roughness on the horizontal surface

Newton's First Law PPT, Part 3: Learning Newton's First Law

Content: All objects always maintain a state of uniform linear motion or a state of rest when they are not acted upon by external forces.

think

If the speed of a moving object is v, how will it move on a smooth plane (resistance is 0)?

If the speed of a moving object is 0, what state will it be in on a smooth plane (resistance is 0)?

So, is it correct to say "force is what maintains the state of motion of an object"?

explain:

⑴ When there is no force on the object, the originally stationary object will remain stationary forever; the originally moving object will move in a straight line with uniform speed.

⑵ Force is what changes the state of motion of an object, not what maintains its motion.

⑶Research method: experiment + reasoning

Newton's first law PPT, part 4 content: thinking and discussion:

1. As shown in Figure 3-55A, when the ball is falling vertically, why is the speed increasing?

As the ball falls vertically, its speed increases because the force (gravity) it receives is consistent with the direction of motion.

2. As shown in Figure 3-55B, when the ball is thrown vertically upward, why does the speed get smaller and smaller?

When the ball is thrown vertically and moves upward, the speed becomes smaller and smaller because of the force (gravity) acting in the opposite direction of the movement.

3. As shown in Figure 3-55C, when the ball is thrown obliquely upward, why does the direction of movement change?

During the motion of the ball being thrown upward obliquely, due to the force (gravity) exerted at an angle to the direction of motion, gravity plays a role in changing the direction of motion.

Newton's First Law PPT, Part 5: Practice

1. Regarding Newton’s first law, which of the following views is correct ( )

A. Experiments to verify Newton's first law can be done, so the law of inertia is correct.

B. The experiment to verify Newton's first law cannot be done, so the law of inertia cannot be definitely correct.

C. An experiment to verify Newton's first law cannot be done, but the law of inertia can be derived through further scientific reasoning based on facts.

D. Although the experiment to verify Newton's first law cannot be done now, one day it can be verified experimentally.

2. Which of the following statements is correct ( )

A. An object must remain stationary without any external force

B. When an object is in motion, it must be acted upon by an external force

C. When an object is not acted upon by any external force, it may be at rest or in motion.

D. None of the above statements are correct

3． An object moves in a straight line at a speed of 1 m/s under the action of a pulling force of 10 N. When all the external forces on the object disappear, the object will ( )

A. stop now

B. Make a uniform linear motion at a speed of 1 m/s

C. Movement is getting slower and slower

D. Not sure

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"Newton's First Law" Motion and Force PPT (Lesson 2):

"Newton's First Law" Motion and Force PPT (Lesson 2) Part One: Classification Practice of Knowledge Points Knowledge Point 1 Inertia 1. Regarding the inertia of an object, which of the following statements is correct ( ) A. Inertia is a property of an object B. An object only has inertia when it is at rest.

"Newton's First Law" Motion and Force PPT (Lesson 1):

"Newton's First Law" Motion and Force PPT (Lesson 1) Part 1: Classification practice of knowledge points Knowledge point 1 The influence of resistance on the movement of objects 1. The football rolling on the ground rolls slower and slower, and finally stops because the football is affected by the _____ on the ground.

"Newton's First Law" PPT download of motion and force:

"Newton's First Law" PPT Download of Motion and Force Part 1 Content: Preview Perception 1. The Effect of Resistance on the Movement of Objects 1. The smoother the horizontal surface, the smaller the resistance the car will experience. The slower the car's speed will decrease, the slower the car will move. The longer. 2. If the car transports...

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Update Time: 2024-09-29

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