A ball with mass m and velocity V collides with a static B ball with mass 3M. The collision may be elastic or inelastic, so the velocity of B ball may be () A. 0.6vB. 0.4vC. 0.2vD. 0.1v
A. If VB = 0.6V, the direction of V is positive, and from the conservation of momentum, we get: MV = MVA + 3M · 0.6V, VA = - 0.8V, the total kinetic energy of the system before collision is EK = 12mv2. After collision, the total kinetic energy of the system is: EK ′ = 12mva2 + 12 · 3mvb2 = 12m (0.8V) 2 + 12 · 3mvb2 > 12mv2
RELATED INFORMATIONS
- 1. Derivation process of stiffness coefficient relationship of series spring? Series connection: stiffness coefficient relation 1 / k = 1 / K1 + 1 / K2 How to deduce? The detailed process is needed If you can, add the parallel derivation process. But the best answer is to look at the series
- 2. What is the perimeter formula of trapezoid
- 3. Area formula for all figures
- 4. Area formula of figure The more detailed it is, the more answers we have in common
- 5. Calculate the area and volume of all figures,
- 6. How to convert building area and residential area? How much is the building area converted into residential area? What is the formula?
- 7. I asked a math problem and suddenly became interested in math. The algorithm for calculating handshake is 7 * 6 / 2 = 21. Then if I only tell you how to calculate the total handshake amount, for example, the total handshake amount is 74
- 8. At the banquet, two people shook hands one by one, a total of 28 times, asked: how many people in total? Such as the title! Requirements: with a quadratic equation solution!
- 9. How many times do 20 students shake hands to greet each other?
- 10. There is a party of ten students. If each of them shakes hands with the others, how many times?
- 11. There is a formula for the conservation of momentum: how can p = √ 2mek be deduced, and under what conditions can it be used?
- 12. Conservation of momentum, conservation of energy A smooth inclined plane with height h and angle a is placed on a smooth horizontal plane, and a slider slides along the inclined plane to the bottom. If the velocity of the inclined plane is V2, the velocity of the slider relative to the inclined plane is V1, Simultaneous: MGH = 1 / 2m (v1sina) ^ 2 + 1 / 2mv2 ^ 2 + 1 / 2m (v1cosa-v2) ^ 2 mv1cosa=(M+m)v2
- 13. How to judge a problem is to use kinetic energy theorem, momentum theorem, energy conservation or energy conservation. What is the ideological basis? How to correctly analyze the problem? How to correct the formula for the problem that can't be solved
- 14. At the initial velocity of V0 = 10m / s, throw a small ball with mass of M = 2kg at an angle of 30 degrees with the horizontal direction, ignoring the effect of air resistance. G is taken as 10m / S ^ 2. Calculate the velocity of the small ball at the end of the second after throwing
- 15. When will high school physics consider using the kinetic energy theorem, the conservation of mechanical energy, the conservation of energy, the conservation of momentum theorem, and the conservation of momentum theorem? And the left hand rule, how to use the right hand rule? And how to use Lenz's law?
- 16. The mass m moves at the velocity V and collides with the mass M. after the collision, the momentum of the mass m is equal to that of the mass M. the mass ratio m m m may be () A. 2B. 3C. 4D. 5
- 17. An object of mass m collides with a stationary object of mass m at its initial velocity v. after the collision, the momentum of the two objects is equal. The possibility of M / M is obtained
- 18. 1. An object is thrown up 420 away from the ground and lands after 10 seconds, 2. The car with mass m moves forward on a smooth horizontal plane with speed V1. There is a man with mass m on it. He asks how fast the car is when the man jumps backward and horizontally from the speed V2 of the car, This involves the relative speed, I think people's speed should be (V1 - V2) But the answer is (v-v2). He sets V to make the speed of the car after jumping. I think the speed can't change suddenly. It should be v1. Why
- 19. The mass of the inclined trolley is m and the height is h. When an object with mass m slides down from the top of the trolley, the speed of the object sliding away from the bottom of the inclined trolley is set as V, regardless of all friction. The following statements are: ① the speed of the object sliding away from the trolley v = 2GH; ② the speed of the object sliding away from the trolley V < 2GH; ③ the speed of the object sliding away from the trolley v = MVM; ④ the speed of the object sliding away from the trolley V < MV M where the correct one is () A. Only (1) and (3) correct B. only (1) and (4) correct C. only (2) and (3) correct D. only (2) and (4) correct
- 20. Momentum: when m and V are constant, only the direction of V changes, then the momentum changes