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It is often used in science to show force directly
A line segment with an arrow
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Diagram and diagram of force:
Object a is clamped between two fixed and identical boards a and B, and can just slide down at a constant speed. With a vertical upward force F = 8N, object a can be pulled out at a constant speed. How much is the gravity of object a and the friction of each board against it?
The gravity is 4N, and the friction force of the board is 2n
If we know that object a can slide down at a constant speed, we can get g = 2F (G is the gravity of object a; F is the friction force of one board against object a, and the two boards are the same)
When the object a is pulled up by the vertical force F, it is pulled out at a constant speed
F=G+2f=8N
From the previous synthesis, it is easy to know: g = 4N; F = 2n. That is, the gravity is 4N and the friction is 2n
What's unclear, so ask more clearly
I may not be able to help you!
If you land on the moon and drive a lunar rover on the surface of the moon, please tell us two different phenomena
1. If you hit an obstacle on the moon, you will fly
2. No matter how fast you accelerate, the car doesn't go very far
The car on the horizontal ground weighs 150n. When the car is pulled 20n horizontally to the right, it moves in a straight line at a constant speed. When the horizontal pull is increased to 25N, is the force on the car in the horizontal direction a balance force
No
Because of the uniform linear motion at 20n, the tension and friction force are balanced, and the friction force is equal to the tension force of 20n
And because the roughness of the contact surface does not change and the weight of the car does not change, the friction force on the car in this case is always 20n
So when the force is 25N, the resultant force is 5N, and the direction is horizontal to the right, and the object moves in a straight line with uniform acceleration
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