7.the theory of matter states that all particles of matter are in constant motion.
(fill in the blank)

The kinetic theory of matter states that all particles of matter are in constant motion.

The following are the postulates of kinetic theory of gases:

1.The particles of gases are in constant and random motion. Due to this motion, they collide with each other and walls of the container.

2.The particles of gases have point mass and zero volume.

3.The particles of gases have no such attraction or repulsion between them.

4.The kinetic energy with which the particles are moving is directly proportional to temperature. A temperature increases, kinetic energy also increases, and particles collide each other more frequently.

5.The particle of gases at given temperature have same kinetic energy.

elements make up everything, and they combine to make compounds.

the answer is c

(newtons first law)

conservation of momentum law states :

momentum before collision = momentum after collision

momentum p (kg-m/s)= mass * velocity

say moving car=1 000 kg, velocity = 10 m/s then p = 1 000*10= 10 000 kg-m/s

say still car = 2 000 kg, velocity = 0 m/s then p = 2 000* 0 = 0 kg-m/s

total momentum prior to collision = 10 000 + 0 = 10 000 kg-m/s

momentum after collision = 10 000 kg-m/s

mass now = 1 000 kg+2 000 kg = 3 000 kg

10 000 = 3 000 kg* velocity m/s

10 000/3 000 = velocity

3.33 m/s = velocity after collision

an impulse is a force applied over time , momentum is exclusive of external forces and a perfect collision is implied