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3 years ago

Which of the following is an element?

1 answer:

3 0

Oxygen is on the Periodic Table of Elements as a member of the chalcogen group. It is a chemical element represented by the symbol O.

B would've also been a right answer if it weren't for the Dioxide part.

But the answer is C. Oxygen.

You might be interested in

1) For a positive point charge, the lines radiate ………. . While, for a negative point charge, the lines converge …………. .

ch4aika [34]

Answer:

For a positive point charge, the lines radiate <u>outwards</u>, while for a negative point charge, the lines converge<u> inwards.</u>

Explanation:

A single point charges produces an electric field which has a radial shape.The sign of a charge determines the the direction of the field. In Positive charge have the direction of field is out of the charge and for negative charge, the direction of field is towards the charge.This behavior is in relation to how a positive test charge will experience in a field.

5 0

2 years ago

A track begins at 0 meters and has a total distance of 100 meters. Juliet starts at the 10-meter mark while practicing for a rac

shusha [124]

Answer : The correct option is (D).

Explanation :

Given that,

A track begins at 0 meters and has a total distance of 100 meters. Juliet starts at the 10-meter mark while practicing for a race.

We have to find her position after she runs 45 meters.

From the attached figure,

Let A is the position of Juliet. O is the initial point such that OA = 10 m, AB = 45 m and OP = 100 m.

So, using simple mathematics, it is clear that the position of Juliet after running 45 meters will be 55 m. It is OB in the figure.

So, the correct option is (D) " 55 meters ".

3 0

2 years ago

Read 2 more answers

The current theory of the structure of the

Mariana [72]

Answers:

a) $2.82(10)^{21} kg$

b) $1410 J$

c) $36.62 m/s$

Explanation:

<h3>a) Mass of the continent</h3>

Density $\rho$ is defined as a relation between mass $m$ and volume $V$ :

$\rho=\frac{m}{V}$ (1)

Where:

$\rho=2720 kg/m^{3}$ is the average density of the continent

$m$ is the mass of the continent

$V$ is the volume of the continent, which can be estimated is we assume it as a a slab of rock 5300 km on a side and 37 km deep:

$V=(length)(width)(depth)=(5300 km)(5300 km)(37 km)=1,030,330,000 km^{3} \frac{(1000 m)^{3}}{1 km^{3}}=1.03933(10)^{18} m^{3}$

Finding the mass:

$m=\rho V$ (2)

$m=(2720 kg/m^{3})(1.03933(10)^{18} m^{3})$ (3)

$m=2.82(10)^{21} kg$ (4) This is the mass of the continent

<h3>b) Kinetic energy of the continent</h3>

Kinetic energy $K$ is given by the following equation:

$K=\frac{1}{2}mv^{2}$ (5)

Where:

$m=2.82(10)^{21} kg$ is the mass of the continent

$v=4.8 \frac{cm}{year} \frac{1 m}{100 cm} \frac{1 year}{365 days} \frac{1 day}{24 hours} \frac{1 hour}{3600 s}=1(10)^{-9} m/s$ is the velocity of the continent

$K=\frac{1}{2}(2.82(10)^{21} kg)(1(10)^{-9} m/s)^{2}$ (6)

$K=1410 J$ (7) This is the kinetic energy of the continent

<h3>c) Speed of the jogger</h3>

If we have a jogger with mass $m=77 kg$ and the same kinetic energy as that of the continent $1413 J$ , we can find its velocity by isolating $v$ from (5):

$v=\sqrt{\frac{2 K}{m}}$ (6)

$v=\sqrt{\frac{2 (1413 J)}{77 kg}}$

Finally:

$v=36.62 m/s$ This is the speed of the jogger

5 0

3 years ago

It is correct to say that impulse is equal toA) momentum.B) the change in momentum.C) the force multiplied by the distance the f

Elena-2011 [213]

Answer:

B) the change in momentum.

Explanation:

The impulse is defined as the product between the force applied on an object (F) and the duration of the collision ( $\Delta t$ ):

$J=F \Delta t$ (1)

We can rewrite the force by using Newton's second law, as the product between mass (m) and acceleration (a):

$F=ma$

So, (1) becomes

$J=ma \Delta t$

Now we can also rewrite the acceleration as ratio between the change in velocity and change in time: $a=\frac{\Delta v}{\Delta t}$ . If we substitute into the previous equation, we find

$J=m\frac{\Delta v}{\Delta t}\Delta t=m\Delta v$

And the quantity $m\Delta v$ is equivalent to the change in momentum, $\Delta p$ .

6 0

3 years ago

When you need to pass a motorcycle, _____________.A. move into the left lane to pass the motorcycle B. pass to the left using th

erma4kov [3.2K]

Answer:

A) move into the left lane to pass the motorcycle

Explanation:

According to law, when it is needed to pass other vehicles, it requires you to only pass other vehicles on the left (using the left lane).

When passing a motorcyclist, remember to give him/her the same full lane width as other vehicles. Never drive in the same lane with a motorcyclist, even if the lane is wide enough to fit your vehicle and the motorcyclist.

5 0

3 years ago