Today we have seven major continents however most geologists dont think it was like this 200 million years ago they think there was just ?

The existence of Pangaea

Explanation:

The geologists believed that the continents that are separated now must have attached together in its geological past, forming a huge landmass which is known as the Pangaea. It was a large supercontinent which was present about 200 to 250 million years back.

This Pangaea has got separated into two subcontinents, namely the Laurasia (Northern subcontinent) and the Gondwanaland (Southern subcontinent), due to the plate tectonic movement.

With the increasing time, these two continents further broken into the present day continents, of which, there are seven major continents and numerous smaller continents.

(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