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How to calculate the work done by an object on an inclined plane? What is the formula?
Uniform motion:
The resultant force of each force on the object is 0
The work of gravity is zero
Work of supporting force of inclined plane = MGS * sinacosa
Work of friction = - MGS * sinacosa (a is inclined angle; s is displacement)
In the formula of physical friction f = UN, what does n mean?
F=uN
U is the coefficient of sliding friction
N is the positive pressure on the contact surface
There are two reasons for friction
1. If the texture of the contact surface is ideal and smooth, there will be no friction
2. Pressure, that is, the force perpendicular to the moving direction of the object, when two rough objects contact, if there is no pressure on the vertical contact surface, there will be no friction
The formula for friction is f = UN. (U is the coefficient of friction, depending on the texture; n is the pressure)
0.75 = (1 / 4) = (9 / 4) = 12 ^ ()
0.75 = (3 / 4) = (9 / 12) = 12 ÷ (16)
Hope to help you_ ∩)O~
If x = - 3, y = 3 is the solution of the system mx-y = 1 2x + NY = 2, then M=_______ ,n=_______ .
-3m-3=1
-6+3n=2
∴m=4/3
n=8/3
999 * 999-1999 = (1000-1) ^ 2-1999 = 1000 ^ 2-2 * 1000 + 1-2000 + 1 = 1000000-2000 + 2-2000 = 996002
①999×999=（1000-1）×（1000-1）=1000×1000＋1000×﹙－1﹚＋﹙－1﹚×1000＋﹙－1﹚
×﹙－1﹚=1000000-1000-1000＋1=998001.
② 998001-1999 = 996002
Using factorization, it shows that the eighth power of 9 minus the twelfth power of 3 can be divided by 80
9^8-3^12
=3^16-3^12
=3^12×(3^4-1)
=80×3^12
So, it's divisible by 80
101+102+103+.+199+200 =
101+102+103+.+199+200
=(101+200)*100/2
=301*50
=15050
The bottom diameter of a cylinder is 2 decimeters, the surface area is 12.56 square decimeters, and the height of the cylinder is______ Decimeter
Bottom area: 3.14 × (2 △ 2) 2 = 3.14 (square decimeter), side area: 12.56-2 × 3.14 = 6.28 (square decimeter), height: 6.28 △ 2.14 × 1, = 6.28 △ 6.28, = 1 (decimeter); answer: the height of the cylinder is 1 decimeter
Solve the equation X-6 (2x + 1) = 14 + 9 (X-2)
x-6(2x+1)=14+9(x-2)
x-12x-6=14+9x-18
x-12x-9x=14-18+6
-20x=2
x=-0.1
The area of a triangle vegetable field is 30 square meters, and the height is 5 meters. How long is the bottom of this vegetable field?
30 = 1 / 2 * bottom * 5
Bottom = 12
RELATED INFORMATIONS
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