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madam [21]
3 years ago
6

Please help me I need these extra credit points plz plz plz

Physics
2 answers:
KengaRu [80]3 years ago
6 0

Answer:

2 half lives have passed, the rock layer is 4,000 years old

Explanation:

It takes 2,000 years for half of the 400 atoms to decay which leaves you with 200 atoms. It then takes another 2,000 years for half of the 200 atoms to decay with leaves you with 100 atoms after a total of 4,000 years and 2 half lives.

VashaNatasha [74]3 years ago
5 0
Two half lives so it is 4000 years old
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<h3>How to use Newton's laws?</h3>

The second Newton's law states that:

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Where acceleration is the rate of change of the speed. From that equation, we conclude that the acceleration is in the same direction that the net force.

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If we don't know that, we can't find the direction of motion.

An example of this can be a car going at 100km/h east-wise.

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2 years ago
A small glass bead has been charged to + 30.0 nC . A small metal ball bearing 2.60 cm above the bead feels a 1.80×10−2 N downwar
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