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If two objects have the same momentum, they must have () A. the same velocity B. the same mass C. the same direction of motion If two objects have the same momentum, they must have () A. Same speed B. same mass C. Same direction of motion D. same acceleration
(1) according to P = MV, the momentum is the same, if the mass is the same, then V should be the same; and because momentum and velocity are vectors, "the same velocity" should include the same size and direction at the same time
If a 2kg mass object is thrown horizontally at an initial velocity of 10m / s, what is the momentum of the object at the end of 1s, kg.m/s, and what is the direction
After 1s, the vertical velocity is 10m / s, the combined velocity is 10 * root, the momentum is 20 * root, 2kg. M / s, and the direction is inclined downward and the horizontal angle is 45 degrees
The mass of the object is m. at the height h above the ground, when it is thrown to the ground at the speed V level, what is the change of momentum?
1)
The change of momentum from throwing to landing = 0-mv = - MV
2)
From throwing to landing - instantaneous momentum change = impulse of gravity Mgt
h=(1/2)gt^2
T = root (2H / g)
From throw to landing - instantaneous momentum change = mg root (2H / g)
The direction of momentum change is vertical and downward
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