Which best describes the modern periodic table?
o
a. it is the same as henry moseley's periodic table.
o
b. it is similar to mendeleev's periodic table, but the elements are
ordered by increasing atomic mass,
o
c. it is the same as dmitri mendeleev's periodic table.
o
d. it is similar to moseley's periodic table, but new elements are
added as they are discovered.

D.

explanation:

as days years months go by more and more new elements that are chemically made or are natural are added even though the ones at school have been updated for such a long period of time

(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