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3 years ago

"Coal mines may contaminate groundwater in a location." What does this statement most likely represent?

Physics

2 answers:

Annette [7]3 years ago

8 0

Answer: an observation

Coal mining is a process of excavation of coal from the deeper layers of the earth crust. The mining process generally involves the unsaturated region but it adversely affect the saturated region, where groundwater reservoir is present. This results in the infiltration of the residues and sediments into the groundwater, hence contaminate it.

The given situation is an observation because it can be based upon facts and evidences.

Aleks04 [339]3 years ago

5 0

By now ... 2018 ... after 200 years of experience and evidence,
it's an observation.

You might be interested in

In his famous experiment, Rutherford fired alpha particles at a thin gold film. Most of the alpha particles went through the fir

ale4655 [162]

Answer:

1. The nucleus is about 1/2 the size of the atom

Explanation:

Alpha particles are positive charge particles and they are bounced back by the nucleus because nucleus is also same size

Now in present experiment Rutherford found that very few alpha particles are bounced back along same path which shows that very small region inside the nucleus is having positive charge and rest part of the atom is empty.

Now if we found that half of the alpha particles are bounced back then it shows that size of the nucleus is very large now as compare to previous one because only nucleus can bounce back the alpha particles

so correct answer will be

1. The nucleus is about 1/2 the size of the atom

5 0

3 years ago

A balloon will stick to a wooden wall if the balloon is charged

grigory [225]

<h2>Answer: either way</h2>

The balloon contains neutral charge atoms, that is, it has the same number of electrons (negative charge), protons (positive charge) and neutrons (no charge).

Then, when two objects come into contact, the electrons of one of them can become part of the other.

Thus, by bringing the balloon closer to the wall, the wall, which is also made up of atoms, will reorder its charges in such a way that its electrons or protons become part of the balloon, charging it.

7 0

3 years ago

The same ball is shot straight up a second time from the same gun, but this time the spring is compressed only half as far befor

Mekhanik [1.2K]

Answer:

The new height the ball will reach = (1/4) of the initial height it reached.

Explanation:

The energy stored in any spring material is given as (1/2)kx²

This energy is converted to potential energy, mgH, of the ball at its maximum height.

If the initial height reached is H

And the initial compression of the spring = x

So, mgH = (1/2)kx²

H = kx²/2mg

The new compression, x₁ = x/2

New energy of loaded spring = (1/2)kx₁²

And the new potential energy = mgH₁

mgH₁ = (1/2)kx₁²

But x₁ = x/2

mgH₁ = (1/2)k(x/2)² = kx²/8

H₁ = kx²/8mg = H/4 (provided all the other parameters stay constant)

6 0

3 years ago

A 5 kg ball is sitting on top of a hill. It has a Potential Energy of 6000J. What is the height of the ball?

natali 33 [55]

Explanation:

mass=5 kg

potential energy=6000j

height=?

Now

potential energy =m.g.h

or 6000=5*9.8*h

or 6000=49h

or 6000÷49=h

or h= 122.45m

6 0

3 years ago

A toy gun uses a spring to project a 4.5-g soft rubber sphere horizontally. The spring constant is 8.0 N/m, the barrel of the gu

marishachu [46]

Answer:

1.93 m/s

Explanation:

Parameters given:

Mass = 4.5g = 0.0045kg

Spring constant = 8.0 N/m

Length of barrel = 13 cm = 0.013m

Frictional force = 0.035N

Compression = 5.8 cm = 0.058m

First, we find the P. E. stored in the spring:

P. E. = ½*k*x²

P. E. = ½ * 8 * 0.058² = 0.013J

Then, we find the work done by the frictional force while the sphere is leaving the barrel of the gun:

Work = Force * distance

The distance here is the length of the barrel.

Work = 0.035 * 0.13 = 0.0046 J

The kinetic energy of the sphere can now be found:

K. E. = P. E. - Work done

K. E. = 0.013 - 0.0046 = 0.0084J

We can now find the speed using the formula for K. E.:

K. E. = ½*m*v²

0.0084 = ½ * 0.0045 * v²

v² = 0.0084/0.00255 = 3.733

=> v = 1.93 m/s

4 0

3 years ago

Read 2 more answers