A scientific theory never changes. ture or false ?

False.

Explanation:

Scientific theories and hypothesis are all tentative. Science tries to prove something is either true of false and come up with answers (as much as we can) for many problems. Sometimes they are made based on limited data or information. Over the years, we come up with need findings discoveries which are able to give us more information and give us better answers. There have been a couple of scientific laws which had to be completely revised or discarded after new observations. An example of this would be the Laws of Thermodynamics. A couple of the laws have been changed over the decades after scientists made new disoveries and observations.

(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