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3 years ago

5

A student has an 80 g sample of a radioactive material that has a half-life of 20 seconds. How much material will he have left a

fter 60 seconds?
A.
10 g

B.
20 g

C.
40 g

D.
5 g

1 answer:

Juliette [100K]3 years ago

7 0

The answer is C 40 g

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Hi there!

$\large\boxed{\text{B) 20 meters}}$

We know that:

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K = Kinetic Energy (J)

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At 10m, the total amount of energy is equivalent to:

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2 years ago

Diferencie energia cinética de energia potencial gravitacional.

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4 years ago

A speedboat moves on a lake with initial velocity vector v1,x = 8.57 m/s and v1,y = -2.61 m/s, then accelerates for 6.67 seconds

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First, you find the velocity at each component. The general equation is:

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To find the final speed, find the resultant velocity by taking the hypotenuse.

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3 0

4 years ago

Below is a circuit schematic of sources and resistors (Figure 3). VS = 10V , R1 = 100Ω, R2 = 50Ω, R3 = 25Ω, IS = 2A. Calculate t

lorasvet [3.4K]

Answer:

$V_3\approx 4.28\,\,V$

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10 V - 4.28 V = 5.72 V

and with this info, we can calculate the current through R1 using Ohm's Law:

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4 years ago