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3 years ago

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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2 years ago

2) How much work is required to pull a sled 15<br> meters if you use 30N of force?

geniusboy [140]

2 people

Explanation:

7 0

3 years ago

It may seem strange that the selected velocity does not depend on either the mass or the charge of the particle. (For example, w

Charra [1.4K]

Answer:

b) q large and m small

Explanation:

q is large and m is small

We'll express it as :

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As we know the formula:

F = Eq

And we also know that :

F = Bqv

F = $\frac{mv^{2} }{r}$

Bqv = $\frac{mv^{2} }{r}$

or Eq = $\frac{mv^{2} }{r}$

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3 years ago

A catamaran with a mass of 5.44×10^3 kg is moving at 12 knots. How much work is required to increase the speed to 16 knots? (One

Andre45 [30]

The work that is required to increase the speed to 16 knots is 14,176.47 Joules

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5.44×10^3 kg = 12 knots

For an increased speed to 16knots, we will have:

x = 16knots

Divide both expressions

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