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Mashutka [201]
3 years ago
6

When were the following metals discovered:

Physics
1 answer:
Katen [24]3 years ago
3 0

Answer:

A. 4000 BC

B. January 24, 1848

C. 1400 BC

Explanation:

Please mark brainliest.

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Need help y’all ASAP please...physics
dolphi86 [110]

Answer:

t = 3/8 seconds

Explanation:

h=-16t^2 - 10t+6

h= 0 when it hits the ground

0=-16t^2 - 10t+6

factor out a -2

0= -2(8t^2 +5t -3)

divide by -2

0 = (8t^2 +5t -3)

factor

0=(8t-3) (t+1)

using the zero product property

8t-3 = 0    t+1 =0

8t = 3         t= -1

t = 3/8     t= -1

t cannot be negative  ( no negative time)

t = 3/8 seconds

3 0
3 years ago
The alternative to nuclear fission reactors in a nuclear fusion reactor. Explain why it is much more difficult to get a fusion r
Sliva [168]

Answer: The major challenges are as

1) understanding of the plasma: Plasma is a soup like mixture of subatomic particles of different atoms nuclei and electrons that are shattered apart by the temperature at which plasma is formed. further research is needed to understand the behavior of plasma so that it can be put to a proper use.

2) Confinement of plasma: Once we get the plasma we need to hold it so that we can obtain heat from it to drive a steam turbine but the sheer temperature of plasma is in millions of Celsius thus currently making it impossible to confine conventionally. Scientists use a loop of electric and magnetic fields to keep it in circulatory like manner so that it can be studied.

3) finally to obtain electricity from the plasma it should be stable to produce electricity. But currently to obtain pressure, temperature so that we have a sustained supply is highly difficult in technical and economical aspects.

Inertial confinement: In order to get the nuclei of atoms close enough for fusion this type of method used compression of the nuclei into highly small volumes.This is accomplished by use of lasers which are directed towards the fuel pellets that implode and travel towards other nuclei making fusion possible. It's main advantage is that it requires lesser time to initiate fusion but the disadvantage being that a large power is used to fire the lasers and the lasers should all hit the small target.

Magnetic Confinement: In this method we use a magnetic and electric fields in a properly designed space to keep the plasma in motion. In motion the nuclei of the atoms come close enough to initiate fusion.It's advantage being less power is required to start the process as compared to inertial confinement and the disadvantage being that plasma confinement is currently not properly understood.

5 0
3 years ago
1. What layer of the Earth is<br> flowing, solid and plastic?
melisa1 [442]

Answer:

The mantle

Explanation:

The mantle is a plastic solid of varying densities which allow convection currents to flow molten rock towards the earth's surface resulting in volcanic activity, tectonic plate movement, earthquakes, and movement of continents.

5 0
3 years ago
Read 2 more answers
A particle moving in the x direction is being acted upon by a net force f(x)=cx2, for some constant
makkiz [27]
The work-energy theorem states that the change in kinetic energy of the particle is equal to the work done on the particle:
\Delta K = W
The work done on the particle is the integral of the force on dx:
W= \int\limits^{3L}_L {F(x)} \, dx = \int\limits^{3L}_L {cx^2} \, dx = \frac{26}{3}cL^3
So, this corresponds to the change in kinetic energy of the particle.
6 0
3 years ago
Can someone please help me it would mean alot​
Lunna [17]
It’s the wavelength I believe
7 0
3 years ago
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