"Elasticity" force PPT

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"Elasticity" force PPT

Part One Content: Basic Knowledge Key Points

Knowledge point 1 Elasticity

1. If the rubber band is pulled hard, the rubber band will deform, and will return to its original shape when no force is applied, indicating that the rubber band has undergone elastic deformation.

2. The basketball hits the backboard and is bounced back. The force that causes the ball to bounce back is due to the elastic deformation of the backboard. This force is called elastic force.

3. Conditions for elasticity: (1) mutual extrusion; (2) elastic deformation.

4. Regarding elasticity, which of the following statements is wrong (B)

A. Elastic force exists only between objects that are in contact with each other and deformed.

B. Only objects acted upon by springs are acted upon by elastic force

C. Elastic force refers to the force that an object that undergoes elastic deformation exerts on the object that contacts it because it wants to return to its original shape.

D. The direction of elastic force is always opposite to the direction in which the object exerting force recovers its deformation.

Knowledge point 2 Spring dynamometer

5. As shown in the figure, the pointer of the spring dynamometer being used points to a certain position. The measuring range of this spring dynamometer is 0~5 N, the graduation value is 0.2 N, and the force indicated by the spring dynamometer is F=1.4N.

6. Within the elastic limit, which of the following statements is correct (B)

A. The smaller the tension on the spring, the longer the extension of the spring.

B. The greater the tension on the spring, the longer the spring will stretch.

C. The elongation of the spring has nothing to do with the tension on the spring.

D. None of the above statements are correct

7. Regarding the spring dynamometer, which of the following statements is incorrect (C)

A. The measured force cannot exceed the measuring range.

B. The spring axis of the dynamometer should be consistent with the direction of the measured force.

C. Can directly measure the mass of an object

D. Zero point should be calibrated before use

Elasticity PPT, Part 2: Improvement of Comprehensive Ability

8. As shown in the figure, when the athlete presses down on the springboard, the springboard deforms elastically (optional "elastic" or "plastic"), resulting in an upward (optional "up" or "down") movement. Elasticity.

9. When there is no tension on a spring dynamometer in the laboratory, its pointer points to the position shown in Figure A. At this time, the indication is 0.4 N; if this spring dynamometer is used to measure the force of a wooden block on the spring The tensile force of the dynamometer, as shown in Figure B, will be larger than the actual value (please fill in "large" or "small").

10. Take a hacksaw blade, press one end on the table with your fingers, and extend the other end out of the table. Use your fingers to press down to the two positions a and b as shown in the picture. After you let go, the hacksaw blade can return to its original shape. In the scenario, the fingers feel the greater force when bending the hacksaw blade to position b (optional "a" or "b"). This phenomenon shows that the greater the elastic deformation of the object, the greater the elastic force generated.

11. Among the following forces, the one that is not elastic is (C)

A. The pulling force of the wire on the lamp

B. The support of the tabletop to the tea cup

C. The attraction between two magnets

D. The pressure of the book on the desktop

12. Several students used a tensioner to test their arm strength. As shown in the picture, everyone was not to be outdone. As a result, everyone could hold their arms straight, then (A)

A. People with longer arms use greater pulling force

B. People with stronger arms use greater pulling force.

C. Heavier people use greater pulling force

D. Everyone uses the same pulling force

13. There is a spring scale. When there is no force on the hook, the pointer does not point at the zero mark position, but at the position of 0.2 N. At this time, pull the hook of the spring scale by hand so that the reading of the spring scale is 4 N. , then the force of hand pulling the spring is (C)

A.4.2 N B.4 N

C.3.8 N D. Unable to determine

14. When measuring a force of 6 N, the most appropriate specification of the spring dynamometer should be (B)

A. Measuring range 15 N, graduation value 0.5 N

B. Measuring range 10 N, graduation value 0.2 N

C. Measuring range 5 N, graduation value 0.1 N

D. The above three spring dynamometers are all available

Elasticity PPT, the third part: expansion, exploration and breakthrough

20. When an extracurricular study group was exploring the "relationship between the elongation of the spring and the tensile force", the experimental data were as shown in the table.

Tensile force F/N 0 0.5 1 1.5 2 2.5 3 3.5 4

Spring length/cm 22 23 24 25 26 27 28 28.5 28.6

(1) Use such a spring to make a dynamometer with a measuring range of 0~3 N;

(2) Within a certain range, the mathematical expression of the relationship between the tension F and the elongation ΔL of the spring is F=(0.5 N/cm)•ΔL;

(3) When the object is suspended, the length of the spring is 25.5 cm, then the force of the object pulling the spring downward is 1.75N.

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For more information about the "Force and Elasticity" PPT courseware, please click on the "Force ppt and Elasticity ppt" tab.

"Elasticity" force PPT download:

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Update Time: 2024-11-22

This template belongs to Physics courseware People's Education Edition Physics for Grade 8, Volume 2 industry PPT template

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