the atom of an element x has 21protrons and 23neutrons. What is the
(a) Electron number
(b) Mass number
(c) Neutron number​

Answers

Answer 1
A. 21 electrons
B. 44
C. 23 neutrons

Related Questions

Hi please zoom in to see it clearly, uh you don’t have to answer them all but it would be nice !!! (no links please) :D

Answers

12.could be D
13.A
14.D
15.C
16.A

In a nuclear fusion reaction, atoms:
split apart.
combine.
explode.
cool down.

Answers

The answer is combine
The correct answer is B. Combine

Although planets orbit the Sun in ellipses, all the planetary orbits are fairly close to circular and not very eccentric.


True
False

Answers

Answer:

False

Explanation:

The Sun rotates in this same, right-hand-rule direction. All planetary orbits lie in nearly the same plane. All planetary orbits are nearly circular (eccentricity near zero).

Rate as Brainliest please

Why is it imperative that the collision takes place in a plane parallel to the plane containing the camera lens

Answers

Answer:

It is imperative that the collision takes place in a plane parallel to the plane containing the camera lens so that parallax does not affects the recording of camera.

Explanation:

It is imperative that the collision takes place in a plane parallel to the plane containing the camera lens so that parallax does not affect the recording of the camera. There may occur an error in video analysis if the camera is tilted at an angle in relation to the collision plane.

(The role of the lens is to take light to a fixed focal point.)

Telescopes are used for producing images, spectroscopy, and time monitoring of celestial objects.


True
False

Answers

Your answer is true.

Hope I could help

a disk of a radius 50 cm rotates at a constant rate of 100 rpm. what distance in meters will a point on the outside rim travel during 30 seconds of rotation?​

Answers

Each minute, the disk completes 100 revolutions, so a point on the rim traverses a distance of 100 times the circumference of the disk and would have a linear speed of

100 rev/min

= (100 rev/min) × (2π × 50 cm/rev) × (1/100 m/cm) × (1/60 min/s)

= 5π/3 m/s ≈ 5.236 m/s

Then after 30 s of rotation, the point would have traveled a distance of

(5π/3 m/s) × (30 s) = 50π m ≈ 157.08 m

A 2.5 Coulomb charge is placed in an electric field where it experiences an electrical force of 50.N. What is the value of the electrical field at the place where the charge is located?
Remember to identify all data (givens and unknowns), list equations used, show all your work, and include units and the proper number of significant digits to receive full credit. (5 points)

Answers

Answer: E= 20 N/C

Explanation: Charge q = 2.5 C , force F = 50 N. F = qE and

E= F/q= 50N / 2.5 C = 20 N/C

2. Plastic is a great conductor of charge so it moves quicker.

True
False

Answers

Answer:

the answer is false

Explanation:

plastic doesnt conduct anything

Which option identifies the specific knowledge that the team in the following scenario must possess?


A team of engineers is designing a space probe that will go to Saturn and collect atmospheric samples. The temperature and atmosphere on Saturn are much different from the conditions on Earth.



(A) The team must have a vast knowledge of thermodynamics.

(B) The team must have a vast knowledge of propulsion.

(C) The team must have a vast knowledge of fluid power systems.

(D) The team must have a vast knowledge of acoustics.

Answers

Answer:

The team must have a vast knowledge of thermodynamics

Explanation:

Just took the test!!!

Answer:

C. Thermodynamics

Explanation:

A man walks 30 m to the west, then 5 m to the east in 45 seconds.
What is his average speed?

Answers

The displacement is the distance from the beginning point to the ending point. The time was just to throw you off. If he walks 30m due west, and then 5m due east, his displacement would be 30-5=25m to the west.

A step-down transformer has 2500 turns on its primary and 5.0 x 10' tums on its secondary. If the potential difference across the primary is 4850 V, what is
the potential difference across the secondary?

Answers

Answer:

I dont know sorry

Explanation:

hehe

Easy question I’ll give extra points. Help

Answers

Answer:

the answer is A

I wish you a good day!

Answer:

THe answer is graph 2 as it represents the puck going in a linear motion

Explanation:

A tabletop two-slit interference experiment consists of a laser pointer shining through two narrow, closely spaced slits in an opaque barrier. The light from the slits produces a characteristic pattern of alternating bright and dark regions on a nearby wall. Listed are five ways to modify the parameters of the experiment. Match each modification according to the effect it would have on the spacing between the bright spots on the wall. In each case, assume that everything else is held constant.

a. Causes the spacing between the bright spots on the wall to increase.
b. Causes the spacing between the bright spots on the wall to decrease.
c. Has effed on the spacing between the bright spots on the wall.

1. increasing the distance d between the two slits in the barrier
2. increasing the brightness of the laser light
3. increasing the distance L from the slits to the wall
4. increasing the distance x from the laser to the slits
5. increasing the wavelength of the laser light

Answers

Answer:

a - 3, 5

b - 1

c - 2, 4

Explanation:

a). The distance between fringes on the screen

        [tex]$y = \frac{m \lambda L}{d}$[/tex]

where, λ is wavelength, m is order of pattern, L is distance between slit and screen, d is separation between slits.

Now we analyze that spacing between bright spots increases as increasing distance L from slits to wall and increasing the wavelength of the laser light, λ.

b). The spacing between the bright spots decreases as the distance between the two slits increases.

c). Has no effect on the spacing between the bright spots on the wall by increasing the distance from the laser to the slits as well as increasing the brightness of the laser.

When does a rubber band, which has been shot at a wall, have the most potential energy?
A When it is lying on the floor.
B When it is flying across the room.
C When it hits the wall.
D When it is stretched ready to shoot at the wall.

Answers

D When it is stretched ready to shoot at the wall

Answer:

C because that requires lots of energy

NEED TO SUBMIT THIS IN 10 MINS, PLS HELP!!!!​

Answers

Answer:

Your answer is B

because it's on sneel's law.

that is sin of incident ray / sin of refracted ray is refractive index

2) Which of the following is not a quality of a healthy relationship?
A) respect
B) trust
C) closed communication
D) honesty

Answers

the answer should be the letter C...
A. Respect periodddd

lus
A cup has a mass of 0.0650 kg and a
volume of 0.000250 m3, and is floating
in fresh water. Pennies are put into the
cup until the top of the cup is level with
the water line. What is the mass of the
pennies in the cup?
[?] kg
Pwater = 1,000 kg/m3

Answers

Answer:

hey but the person at the top is right

Answer:

0.185

Explanation:

Volume of water displaced = 0.000250 ( volume of cup )

Mass of water displaced by cup = density of water X volume of water displaced

= 1000 X 0.000250 = 0.250 kg

Mass of water displaced = mass of cup + mass of pennies ( law of flotation)

0.25 = 0.0650 + mass of pennies

Mass of pennies = 0.2500 - 0.0650

= 0.185 kg

Don’t hesitate to like and rate this answer. It would mean a lot for me.

Easy physics question help.!!!

Answers

Answer: This is not easy lol

Explanation:

try using socratic it is very helpful

HELP PLEASEEE it’s due soon

Answers

Answer:

254.982J

Explanation:

mass = 130kg

gravity = 9.807m/s^2

height = 0.200m

Answer:

potential energy = 254.8 joule

Explanation:

mass (m) = 130 kg

height (h) = 0.200 m

(g) = 9.8

potential energy = m×g×h

= 130×0.200×9.8

= 254.8 joule

A 4-foot spring measures 8 feet long after a mass weighing 8 pounds is attached to it. The medium through which the mass moves offers a damping force numerically equal to 2 times the instantaneous velocity. Find the equation of motion if the mass is initially released from the equilibrium position with a downward velocity of 7 ft/s. (Use g

Answers

Correct question is;

A 4-foot spring measures 8 feet long after a mass weighing 8 pounds is attached to it. The medium through which the mass moves offers a damping force numerically equal to √2 times the instantaneous velocity. Find the equation of motion if the mass is initially released from the equilibrium position with a downward velocity of 7 ft/s. (Use g = 32 ft/s²)

Answer:

x(t) = 7te^(-2t√2)

Explanation:

We are given;

Weight; W = 8 lbs

mass; m = W/g

g = 32 ft/s²

Thus;

m = 8/32

m = ¼ slugs

From Newton's second law we can write the equation as;

m(d²x/dt²) = -kx - β(dx/dt)

Rearranging this, we have;

(d²x/dt²) + (β/m)(dx/dt) + (k/m)x = 0

Where;

β is damping constant = √2

k is spring constant = W/s

Where s = 8ft - 4ft = 4ft

k = 8/4

k = 2

Thus,we now have;

(d²x/dt²) + (√2/(¼))(dx/dt) + (2/(¼))x = 0

>> (d²x/dt²) + (4√2)dx/dt + 8x = 0

The auxiliary equation of this is;

m² + (4√2)m + 8 = 0

Using quadratic formula, we have;

m1 = m2 = -2√2

The general solution will be gotten from;

x_t = c1•e^(mt) + c2•t•e^(mt)

Plugging in the relevant values gives;

x_t = c1•e^(mt) + c2•t•e^(mt)

At initial condition of t = 0, x_t = 0 and thus; c1 = 0

Also at initial condition of t = 0, x'(0) = 7 and thus;

Since c1 = 0, then c2 = 7

Thus,equation of motion is;

x(t) = 7te^(-2t√2)

May you please help?​

Answers

Choice-A is the main reason that people use the thing in the picture.

A fixed 14.1-cm-diameter wire coil is perpendicular to a magnetic field 0.52 T pointing up. In 0.28 s , the field is changed to 0.23 T pointing down. Part A What is the average induced emf in the coil

Answers

Answer:

the average induced emf in the coil is 0.016 V.

Explanation:

Given;

diameter of the wire, d = 14.1 cm = 0.141 m

change in magnetic filed strength, dB = 0.52 T - 0.23 T = 0.29 T

change in time, dt = 0.28 s

The area of the wire is calculated as follows;

[tex]A = \frac{\pi d^2}{4} \\\\A = \frac{\pi \times (0.141)^2}{4} \\\\A = 0.0156 \ m ^2[/tex]

The induced emf is calculated as follows;

[tex]emf = \frac{dBA}{dt} \\\\emf = \frac{0.29 \times 0.0156}{0.28} \\\\emf = 0.016 \ V[/tex]

Therefore, the average induced emf in the coil is 0.016 V.

I WILL GIVE BRAINLIEST TO CORRECT ANSWER
Two boxes are being pulled to the right by a force F across a frictionless table. The force is acting directly on M 2 which is connected to M 1 by a massless cord. Which of the following expressions best represents the acceleration of M 1?

Answers

sorry i don’t know, i really need the points

A wave has a frequency of 67 Hz and a wavelength of 7.1 meters. What is the speed of this
wave?

Answers

the answer hopes this helped

Answer:

475.7 m/s

Explanation:

Given,

Frequency ( f ) = 67 Hz

Wavelength ( λ ) = 7.1 m

To find : Speed ( v ) = ?

Formula : -

v = f λ

v

= 67 x 7.1

= 475.7 m/s

Therefore,

the speed of the wave is 475.7 m/s.

WILL GIVE BRAINLIEST, ANSWER WITH ACTUAL ANSWER OR ELSE I WILL REPORT YOU!!!!!
Four students are assigned a project for which they must experimentally determine the coefficient of kinetic friction between a block of an unknown material and a table. Each student has their own idea of how to go about setting up the experiment. The group settles on two possible test to conduct: Student A's idea and Student B's idea. Student A believes the group can obtain the coefficient of kinetic friction by attaching a spring scale to the mass and pulling on the mass with the spring scale with a horizontally directed force. The reading on the spring scale at the moment the block begins to move is the coefficient of kinetic friction. Which of the following explains what is wrong with Student A's logic?

MC Options inserted in image below

Answers

Answer:

I know you said not to do this but I am doing a challenge and You asked this an hour ago. PLS DON'T REPORT ME.

Explanation: Sorry

Fill in the blanks using the following words: Solid, Liquids, Gasses, More, Less, Gas, Fluids, Higher, Lower, Sun, Radiation, Conductors

● Radiation transfers heat best through _________ because there is _______ space between the particles.

● Conduction transfers heat best through _______ because there is space between the particles.

● Convection transfers heat best through _______ which includes _______ and ______.

● Heat always moves from _________ temperature to _________ temperature.

● Heat from ______ travels to earth by ___________.

● Solids that transfer heat well ate known as _____________.

Answers

Answer:

Blank 1: Gasses

Blank 2: More

Blank 3: Solids

Blank 4: Fluids

Blank 5: Liquid

Blank 6: Gas

Blank 7: Higher

Blank 8: Lower

Blank 9: Sun

Blank 10: Radiation

Blank 11: Conductors

P.S. order of answers does not matter between Blank 5 and 6.

When you look at the backside of a shiny teaspoon held at arm's length, do you see yourself upright or upside down? (b) When you look at the other side of the spoon, do you see yourself upright or upside down? Assume in both cases that the distance between you and the spoon is greater than the focal length of the spoon.

Answers

Answer:

a) The back spoon gives a right image (upright)

b) the front gives an inverted image

Explanation:

The spoon is a curved metallic object, when we see ourselves from the back we have a convex mirror, in this type of mirror when the law of reflection is applied the rays diverge therefore the eye-brain system forms the image with the prolongation of the rays, therefore the image is straight and smaller than the object.

When we look through the deep side of the spoon, we have a concave mirror and as the object (we) is further away than the distance, the rays converge to a point, so the image is real, inverted smaller than the object.

In summary.

a) The back spoon gives a right image (upright)

b) the front gives an inverted image

A scientist measuring the resistivity of a new metal alloy left her ammeter in another lab, but she does have a magnetic field probe. So she creates a 4.5-m-long, 2.0-mm-diameter wire of the material, connects it to a 1.5 V battery, and measures a 3.0 mT magnetic field 1.0 mm from the surface of the wire. What is the material's resistivity

Answers

Answer:

[tex]3.49\times 10^{-8}\ \Omega\text{m}[/tex]

Explanation:

r = Radius = [tex]\dfrac{2}{2}=1\ \text{mm}[/tex]

B = Magnetic field = 3 mT

1 mm = Distance from the surface of the wire

V = Voltage

x = Distance from the probe = [tex]r+1=1+1=2\ \text{mm}[/tex]

R = Resistance

L = Length of wire = 4.5 m

Magnetic field is given by

[tex]B=\dfrac{\mu_0I}{2\pi x}\\\Rightarrow I=\dfrac{B2\pi x}{\mu_0}\\\Rightarrow I=\dfrac{3\times 10^{-3}\times 2\times \pi 2\times 10^{-3}}{4\pi 10^{-7}}\\\Rightarrow I=30\ \text{A}[/tex]

Voltage is given by

[tex]V=IR\\\Rightarrow R=\dfrac{V}{I}\\\Rightarrow R=\dfrac{1.5}{30}\\\Rightarrow R=0.05\ \Omega[/tex]

Resistivity is given by

[tex]\rho=\dfrac{RA}{L}\\\Rightarrow \rho=\dfrac{0.05\times \pi (1\times 10^{-3})^2}{4.5}\\\Rightarrow \rho=3.49\times 10^{-8}\ \Omega\text{m}[/tex]

The resistivity of the material is [tex]3.49\times 10^{-8}\ \Omega\text{m}[/tex].

Acellus
What are harmful substances in the air,
soil, and water called?
A. pollutants
B. toxins
C. carcinogens
D. mutants

Answers

I think it’s A
Hope that helped XD

An elevator motor provides 45.0 kW of power while lifting an elevator 35.0 m. If the elevator contains seven passengers each with an average mass of 70.0 kg and it takes 20.0 s to accomplish this task, determine the mass of the elevator.

Answers

Find how much work ∆W is done by the motor in lifting the elevator:

P = ∆W / ∆t

where

P = 45.0 kW = power provided by the motor

• ∆W = work done

• ∆t = 20.0 s = duration of time

Solve for ∆W :

W = Pt = (45.0 kW) (20.0 s) = 900 kJ

In other words, it requires 900 kJ of energy to lift the elevator and its passengers. The combined mass of the system is M = (m + 490.0) kg, where m is the mass of the elevator alone. Then

W = M g h

where

g = 9.80 m/s² = acceleration due to gravity

h = 35.0 m = distance covered by the elevator

Solve for M, then for m :

M = ∆W / (g h) = (900 kJ) / ((9.80 m/s²) (35.0 m)) ≈ 2623.91 kg

m = M - 490.0 kg ≈ 2133.91 kg ≈ 2130 kg

Other Questions
What is the difference of 95,216 and 35,535? a59,681 b60,321 c60,781 D130,751 an aquarium measures 16 in. 8 in. 10 in. how many liters of water does it hold? how many gallons? When a firm produces 600 widgets with total cost of $1,300 andfixed cost of $800, what is the average variable cost? Part AHow does Sandra Cisneros use foreshadowing in "A House of My Own"?to tell readers about events that happened in the pastto add dramatic tension by building anticipation for future eventsto appeal to the fives senses of her readersto give her work a poetic rhythm and paceQuestion 2Part BWhich answer choice best describes the effect of Cisneros using foreshadowing as identified in Part A?She discusses writing three stories in one weekend at Iowa, which later connects with friends workshopping stories in her apartment, to show readers how dedicated she is to her craft.She tells of her job teaching students in her mother's old neighborhood, which later connects with her encouraging a promising student, to show readers her pride in her Hispanic heritage.She describes of a visit back home for Sunday dinner, which later connects with her sadly surveying her own shabby apartment, to show readers her deep fear that she will never be successful.She describes a visit from her friend Norma, who later admires her collection of thrift-store items and her ability to live on her own, to show readers that she has indeed become self-sufficient. I need help with this question please! PLEASE HELP I GOT IT WRONG EARLIER AND THE WRONG ANSWER WAS H PLS HELP!! Question 3 of 7 < > View Policies Current Attempt in Progress At December 31, 2021, Cullumber Company had a five-month, 5%, $74,400 note receivable that was issued on October 1, 2021. Interest and principal are payable at maturity on March 1, 2022. Prepare the December 31, 2021, adjusting entry for accrued interest. (Credit account titles are automatically indented when amount is entered. Do not indent manually. If no entry is required, select "No Entry" for the account titles and enter O for the amounts) Date Account Titles and Explanation Dec. 31 -17 E (To accrue interest at year-end) Debit Credit What makes up the biodiversity of the Amazon rain forest? PLEASE HELP ME! 20 POINTS! NO BOTS -.- HELP!!! answer quickly pls Assume the following: the investor's required rate of return is 13.5 percent, the expected level of earnings at the end of this year (E) is $6, the retention ratio is 40 percent, the return on equity (ROE) is 15 percent (that is, it can earn 15 percent on reinvested earnings), and similar shares of stock sell at multiples of 8.000 times earnings per share. Questions: a. Determine the expected growth rate for dividends. b. Determine the price earnings ratio (P/E). c. What is the stock price using the P/E ratio valuation method? d. What is the stock price using the dividend discount model? e. What would happen to the P/E ratio (P/E) and stock price if the company increased its retention rate to 75 percent (holding all else constant)? What would happen to the P/E ratio (P/E) and stock price if the company paid out all its earnings in the form of dividends? f. What have you learned about the relationship between the retention rate and the P/E ratios A certain scientific theory supposes that mistakes in cell division occur according to a Poisson process with rate 2.5 per year, and that an individual dies when 196 such mistakes have occurred. Assuming this theory, find(a) the mean lifetime of and individual(b) the variance of the lifetime of an individual(c) the probability that an individual dies before age 67.2(d) the probability that an individual reaches age 90(e) the probability that an individual reaches age 100 Chloe and Ainsley start an art club. The first week they are the only 2 people in the club. They invite more friends to join. Each week the number of people in the club doubles. How many people are in the club on the third week?A. 4B. 6C. 8D. 16 pls help question is on picture Plants and animals have a mutualistic relationship. Explain how. Use the following words to fill in the text (can be used more than once).Anode,Anode to cathode,Battery,Cathode,Chemical to electrical,Electrical to chemical,Electrolysis,Electroplating,Endothermic,Exothermic,N/ANegative,No,Non-Spontaneous,Oxidation,Positive,Reduction,Spontaneous,Yes. Our body is also a good conductorof electricity because of thepresence of ______.Please answer it this is my last question on my test i'll give you 20 points to answer? Eva uses 10 tiles to make a mosaic. Five of the tiles are blue. What fraction, in simplest form, represents the tiles that are blue? can you guys please help me this has to be turned in by 1 !! The french revolution began to a reaction of