![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
It is known that Ma = MB = m, all friction forces can be ignored, and the mass of rope and pulley can be ignored. When a and B are released from rest, and B drops by 3 / 4m, B will lose weight
According to the law of conservation of energy, the reduced potential energy of B is equal to the increased kinetic energy of B + the increased kinetic energy of a + the increased potential energy of A. when B drops by 3 / 4m, a moves by 3 / 8m, and a moves vertically by sin30 * 3 / 8 = 3 / 16m. Because of the moving pulley, the speed of a is 1 / 2 of B. therefore, MB * g * 3 / 4 = 1 / 2 * MB * V ^ 2 + 1 / 2 * ma * (V / 2) ^ 2 + ma
As shown in the figure, objects a and B connected with the light rope cross the fixed pulley, and the mass is ma
Let t be the tension of the rope,
For a: t-mag = MAA
For B: mbg-t = MBA
The acceleration a = (MB MA) g / (MA + MB)
Then t = MAG + MA (MB MA) g / (MA + MB)
So choose B
The mass of the object a on the vertical side is Ma = 0.2kg, and the mass of the object B on the horizontal plane is MB = 1.0kg. The friction between the rope and the pulley is constant, and the OB of the rope is constant
OB part is horizontal, OA is vertical and horizontal, a and B move at a constant speed together, take g = 10. If f pulls object B to the left at an angle of 37 degrees to the horizontal direction, how much pressure does it need to make object a and B move at a constant speed
First, the dynamic friction coefficient u is obtained from the equilibrium equation
Mag-T=0.(1)
T-Mbgu=0.(2)
u=Ma/Mb=0.2
Then the formula 3fu / 5 + Mbgu = 4fu / 5-magu is given by uniform motion
F = 80 / 17 = 4.7n, then object a rises
The mass of two objects is Ma = 2kg, MB = 4kg, the dynamic friction coefficient between a and B is u = 0.2, and the dynamic friction coefficient between B and the ground is u = 0.4
A is on B
Why don't you complete the title
Friction between ab: Fab = Magu (AB) = 2 * 9.8 * 0.2 = 3.92n
Friction between B and the earth: FB = (MA + MB) Gu (b) = (2 + 4) * 9.8 * 0.4 = 23.52n
RELATED INFORMATIONS
- 1. The mass of the two objects is Ma = 2kg, MB = 4kg, the dynamic friction coefficient between a and B is u = 0.2, and the dynamic friction coefficient between B and the ground is u = 0.4, A. The relative sliding occurs between B and the ground, and the friction between the contact surfaces is calculated
- 2. As shown in the figure, two objects a and B are stacked on a smooth horizontal plane. It is known that Ma = 6kg, MB = 2kg, and the dynamic friction factor between a and B is μ = 0.2. A thin line is tied on object a, and the maximum tensile force that the thin line can bear is 20n. Now the thin line is pulled horizontally to the right, g = 10m / S2 Find (1) if the tension is 20n, then the friction between ab? (2) In order to make AB relatively static, the value range of horizontal tension f is calculated
- 3. In this paper, we use the distribution law m (a + B + C) = ma + MB + MC to calculate. Given y ^ 2 + y + 1 = 35 / 6, a + B + C = 36 / 7, we can find a (y ^ 2 + y + 1) +The value of B (y ^ 2 + y + 1) + C (y ^ 2 + y + 1) Speed, online, etc
- 4. Given the points (2,8) and B (6, - 4), find a point m on the x-axis such that Ma = MB, and find the coordinates of point M
- 5. It is known that the real numbers a and B are two of the equation x + m-2 + 1 = 0 about X. find the value of (1 + Ma + a) (1 + MB + b)
- 6. Given that a and B are two of the equations x2 + (M + 2) x + 1 = 0, then the value of (A2 + Ma + 1) (B2 + MB + 1) is______ ．
- 7. Quadratic factorization factor of 4a-12ab + 9b-c Come on, come on
- 8. Given that 14a2 + 9b2 − a + 12b + 5 = 0, find the value of (a − 2) 2A2 − B2
- 9. Let a = {X / (x + 3) (2-x)} > = 0, B = {X / x ^ - 4ax - (1-4a ^)
- 10. Factoring the square of B - the square of 4A 2A (m-n) - 4B (n-m) remember
- 11. If the angle xoy is 60 ° and M is a point in the angle xoy, and the distance from it to ox is Ma = 2, and the distance from it to oy is MB = 11, then OM=_____ I hope it's quick and the process is detailed
- 12. Two high school mathematical inequality questions 1. The known real number A.B.C satisfies a + B + C + D = 3. A ^ + 2B ^ + 3C ^ + 6D ^ = 5 What are the maximum and minimum values of a? 2. If a and B belong to R +, and ab - (a + b) = 1, what is the minimum value of a + B? Thank you very much
- 13. Ask about inequality, A3 + B3 + C3 + 3ABC > 2 (a + b) C2 a > 0, b > 0, C > 0, a + b > C, a, B, C are not equal to each other. Who can help me to prove that? Where A3, B3, C3 is the cube of a, B, C, C2 is the square of C,
- 14. Compare the values of 3x2 + 4 and 2x2 + 4x by collocation method
- 15. When a < 5 is known, the solution set of the inequality ax ≥ 5x + A + 1 is______ ．
- 16. Given f (x) = x & # 178; - x + 43, the real number a satisfies | x-a|
- 17. 1、 ABC are all positive numbers, and a + B + C = 1 1/(a+b)+1/(b+c)+1/(a+c)>=9/2 2、 ABC is a positive number Prove a ^ 2 / B + B ^ 2 / C + C ^ 2 / a > = a + B + C
- 18. Several high school two inequality math problems / urgent! 1. Given 3A ^ 2 + 2B ^ 2 = 5, find the maximum value of y = (2a ^ 2 + 1) (b ^ 2 + 2)? A ^ 2 means the square of A 2. A city uses 37 vehicles to transport a batch of relief materials to the disaster area. Assuming that the speed is v km / h, the route is known to be 400 km long. For safety, the distance between two vehicles should not be less than (V / 20) square kilometers. Then, what is the shortest time for all these materials to reach the disaster area? 3. Let a + B = 1, a > = 0, b > = 0, then the maximum value of a ^ 2 + B ^ 2? A ^ 2 means the square of A 4. Let x > 0, Y > 0, M = (x + y) / (2 + X + y), n = {X / (2 + x)} + {Y / (2 + y)}, then the size relation of M and N? If not, you can only answer yes!
- 19. Given that m and N are real numbers, if the solution set of inequality (2m-n) x + 3m-4n ＜ 0 is x ＞ 49, find the solution set of inequality (m-4n) x + 2m-3n ＞ 0
- 20. The solution of inequality M & # 178; X-1 about X