A, 2 molcules
H2O is one molecule, it has 3 atoms (two hydrogen and one oxygen)
2 H2O are two water molecules
Let the mass of 2500 kg car be 
and it's velocity be 
and the mass of 1500 kg car be 
and it's velocity be 
.
After the bumping the mass be M and it's velocity be V.
By law of conservation of momentum we have
2500 * 5 + 1500 * 1=4000 * V
V = 14000/4000 = 7/2 = 3.5 m/s
So the velocity of the two-car train = 3.5 m/s
Motion of things cause the energy such as the nuclear and the chemicals around temperature traveles
Your answer is 3 ( 1 calcium atom and 2 bromine atoms)
Answer:
Explanation:
Velocity is defined as the rate of change of displacement.
velocity is a vector quantity, that means it requires both magnitude and direction to completely explain the velocity.
For example, the velocity is 5 ms due east, it means an object is moving with speed 5 ms in the direction of east. We can say that the object covers the displacement of 5 m in one second due east.
