All categories

4 years ago

Which statement is true of the carbon atoms that make up a diamond?

2 answers:

8 0

B, this is because the particles in a solid such as the diamond can not move and even though they are locked into place they still vibrate

andrezito [222]4 years ago

4 0

<span>Which statement is true of the carbon atoms that make up a diamond?

Answer: </span><span>B. They are held together and vibrating in place.

Good luck with your studies, I hope this helps!</span>

You might be interested in

A lightning bolt has a current of 56,000 A and lasts for 80 x 10-6 seconds (80 μs). How much charge (in Coulombs) has flowed in

Alina [70]

Answer:

A cloud can discharge as much as 20 coulombs in a lightning bolt.

8 0

3 years ago

Earth, one of eight planets, resides in the spiral galaxy the Milky Way, which is one of the estimated billions of galaxies in s

liberstina [14]

Answer:

One of Eight Planets : Earth

Spiral galaxy, One of the estimated billions of galaxies: Milky Way

Galaxy: Milky Way

Explanation:

According to the definition, appositive or apposition is a grammatical construction which represents similar noun phrases and nouns where one serves or defines the other one.

Here, the ultimate examples of apposition are mentioned in the given statement as Earth: One of Eight Planets, Milky Way: Spiral Galaxy and one of the estimated billions of galaxies: Milky Way.

With such kinds of words, it's easier to understand the noun or renames with a short definition written as a phrase.

6 0

3 years ago

A street light is on top of a 9 foot pole. Joe, who is 3 feet tall, walks away from the pole at a rate of 4 feet per second. At

Gekata [30.6K]

Answer:2 ft/s

Explanation:

Given

Length of Pole is 9 ft

Length of Joe is 3 ft

Joe walks away from Pole at the rate 4 ft/s

Let Joe is x m away from Pole so its shadow length is x'

From Similar triangle concept

$\frac{x'}{x+x'}=\frac{3}{9}$

3x'=x+x'

x=2x'

and it is given $\frac{\mathrm{d} x}{\mathrm{d} t}=4 ft/s$

Differentiating

$\frac{\mathrm{d} x}{\mathrm{d} t}=2\frac{\mathrm{d} x'}{\mathrm{d} t}$

$4=2\times \frac{\mathrm{d} x'}{\mathrm{d} t}$

$\frac{\mathrm{d} x'}{\mathrm{d} t}=2 ft/s$

6 0

3 years ago

How do you rationalize the tension being used in Tennis Racket strings using the concept of impulse and momentum?

zheka24 [161]

Answer:

The momentum, ΔP, and therefore, kinetic energy given to the ball in a serve is the result of the product of the tension force, 'F', in the string and the time of contact, Δt, between the ball and the string

ΔP = F × Δt

Explanation:

The impulse, ΔP, is the produce of the force, 'F', applied to a body for a given period of time, Δt', that gives motion to the body, and it is equal to the change of momentum of the body

ΔP = F × Δt

The momentum, 'P', of a body is the product of the mass, 'm', of the body and its velocity, 'v'

P = m × v

Tension is the axial pulling force of a string

T = Axial Force, F $_{axial}$

The tension used in Tennis Racket strings is between 40 to 65 lbs.

When high tension is used in the string, the string is taut, and the contact duration between the Racket string and the ball is minimal, and the player needs to use more force to obtain a high momentum, and therefore, energy in the ball, which reduces control, and increase stress, as force is more emphasized

When low tension is used in the string, the Tennis Racket strings are more elastic. During a serve, the ball pushes the strings further back into the racket, such that the ball spends more time in contact with the string, (Δt is larger), and therefore, the impulse, F·Δt = ΔP, given to the ball is larger, therefore, the ball has a larger change in momentum, and therefore more energy in the intended direction.

However, a very slackened string will increase the increase area and time (large Δt) of contact of the ball and the racket such that the force given to the ball, F = ΔP/(large Δt) is reduced and therefore reduce the likelihood of gaining points from a serve against an opponent with a much forceful return of a serve.

3 0

3 years ago

If the value of static friction for a couch is 400N, what could be a possible value of its kinetic friction? *

Dafna11 [192]

Answer:

kinetic friction may be greater than 400 N or smaller than 400 N

Explanation:

As we know that maximum value of static friction on the rough surface is known as limiting friction and the formula of this limiting friction is known as

$F_s = \mu_s N$

now when object is sliding on the rough surface then the friction force on that surface is known as kinetic friction and the formula of kinetic friction is known as

$F_k = \mu_k N$

now we know that

$\mu_k < \mu_s$

so here value of limiting static friction force is always more than kinetic friction

also we know that

initially when body is at rest then static friction value will lie from 0 N to maximum limiting friction

and hence kinetic friction may be greater than static friction or if the static friction is maximum limiting friction then kinetic friction is smaller than static friction

so kinetic friction may be greater than 400 N or smaller than 400 N

5 0

4 years ago