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3 years ago

What is the experimental group(s)?

1 answer:

5 0

<h3>I think it B The group(s) that gets the special treatment.</h3><h3 /><h3>I hope this is correct.</h3><h3 /><h3 /><h3 />

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A 16-slug mass is raised by 10 ft. the PE of the mass increased by?

Eva8 [605]

Answer:

<em>The PE of the mass increased by 6,972.95 J</em>

Explanation:

<u>Gravitational Potential Energy</u>

It's the energy stored in an object because of its vertical position or height in a gravitational field.

It can be calculated with the equation:

U=m.g.h

Where m is the mass of the object, h is the height with respect to a fixed reference, and g is the acceleration of gravity or 9.8 m/s^2.

We are given the mass of m=16 slug raised by a height h=10 ft. Both units will be converted to SI standard:

1 slug = 14.59 Kg, thus

16 slug = 16*14.59 Kg=233.44 Kg

1 ft = 0.3048 m, thus:

10 ft = 10*0.3048 m = 3.048 m

Thus, the PE of the mass increased by:

U = 233.44 * 9.8 * 3.048 = 6,972.95 J

the PE of the mass increased by 6,972.95 J

4 0

3 years ago

Because the soles of your shoes have cleats, you can exert a forward force of 100 N even on slippery ice. A 10-kg picnic cooler

Brilliant_brown [7]

Answer:

you must throw 3 snowballs

Explanation:

We can solve this exercise using the concepts of conservation of the moment, let's define the system as formed by the refrigerator and all the snowballs. Let's write the moment

Initial. Before bumping that refrigerator

p₀ = n m v₀

Where n is the snowball number

Final. When the refrigerator moves

pf = (n m + M) v

The moment is preserved because the forces during the crash are internal

n m v₀ = (n m + M) v

n m (v₀ - v) = M v

n = M/m v/(vo-v)

Let's look for the initial velocity of the balls, suppose the person throws them with the maximum force if it slides in the snow (F = 100N), let's use the second law and Newton

F = m a

a = F / m

The distance the ball travels from zero speed to maximum speed is the extension of the arm (x = 1 m), let's look kinematically for the speed of the balls when leaving the arm

v₁² = v₀² + 2 a x

v₁² = 0+ 2 (100/1) 1

v₁ = 14.14 m / s

This is the initial speed for the crash

v₀ = v = 14.14 m / s

Let's calculate

n = M/m v/ (v₀-v)

n = 10/1 3 / (14.14 -3)

n = 2.7 balls

you must throw 3 snowballs

7 0

3 years ago

The lanthanides are all radioactive true or false

Oksi-84 [34.3K]

Answer:

False

Explanation:

All the lanthanides are not radioactive in nature. Just one of the lanthanides are radioactive.

The lanthanides belong to the f-block on the periodic table
Only Promethium in this group are radioactive in nature.
Other elements in the lanthanide series might have radioactive isotopes.

3 0

2 years ago

If John ran a 5-kilometer marathon, how long was that in meters? A. 50 m. B. 5,000 m. C. 500 m. D. 1000 m.

Vladimir79 [104]

The answer is B good lessons

8 0

3 years ago

Read 2 more answers

Find the electron and hole concentrations and fermi level in silicon at 300 k for boron

gogolik [260]

To find the electron and hole concentrations and fermi levels in silicon at 300 k for boron, fermi level is 9.3 x $10^4 cm^-3$ .

<h3>Calculation and Explanation</h3>

Ionization energy for boron in Si, 0.045 eV

Fermi level in silicon,

300 K at $10^{15} cm^{-3}$ (Boron atoms)

All boron impurities are ionized, 300K

Electron, hole concentrations and Fermi levels is found out,

The value of Na = $10^{15} cm^{-3}$

np = $\frac{ni^2}{nA}$

np = $\frac{(9.65 x 10^9)^2}{10^15}$

np= 9.3 x $10^4 cm^-3$

Fermi level is calculated,

Ef - Ev = kT ln(NV/ND)

value of kT = 0.0259 eV (300° K)

So, substitution the values

Ef - Ev = kT ln(NV/ND)

Ef - Ev = 0.0259ln (2.66 x $10^{19} / 10^{15}$ )

Ef - Ev = 0.0259ln (26600)

Ef - Ev = 0.0259 x 10.18

Ef - Ev = 0.263 eV

What is ionization energy?

Ionization energy, also known as ionization energy (IE) or ionization energy (British English spelling), is the minimal amount of energy needed to free the most loosely bonded electron from an isolated gaseous atom, positive ion, or molecule in physics and chemistry.

To know more about ionization energy, visit:

brainly.com/question/16243729

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4 0

11 months ago