1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
alex41 [277]
3 years ago
6

How many neutrons does element X have if its atomic number is 39 and its mass number is 79?

Physics
1 answer:
bazaltina [42]3 years ago
6 0

Number of neutrons: atomic mass - atomic number

Element X's atomic mass is 79 and its atomic number is 39. Subtract 39 from 79 to find how many neutrons Element X has.

79 - 39 = 40

Element X has 40 neutrons.

You might be interested in
Which of the following is true when an object of mass m moving on a horizontal frictionless surface hits and sticks to an object
zhannawk [14.2K]

Answer:

c)

Explanation:

A collision is said to be elastic when the total kinetic energy is the same after the collision. The speed of objects that are stuck together will always be less than the initial speed of the object that was in motion given that the other particle was at rest. It is because the kinetic energy of the system was due to the moving object. The objects have a greater overall mass when they are stuck. If the kinetic energy is the same and the mass increases, the velocity must decrease.

3 0
3 years ago
a brick is suspended above the ground at a height of 6.6 m. it has a mass of 5.3 kg. what is the potential energy of the brick
Svetradugi [14.3K]
The formula for potential energy is
E(p) = mgh

(Mass x gravity x height)

Therefore energy = (5.3)(9.8)(6.6)
= 342.8 J

How did I get 9.8?
9.8 is the constant for gravity
8 0
4 years ago
¿ cuales son las especies q mas características tienes en común ?
Katena32 [7]
De los reptiles, anfibios; pájaros, peces; mamíferos y artrópodos, los que más se asemejan en características son los pájaros y los mamíferos porque ambos son de sangre caliente y no varia independientemente de en qué ambiente se encuentre
5 0
3 years ago
Question I. SUHU ULT
Lilit [14]

Answer:

Feathers are great thermal insulators.

Explanation:

Feathers are great thermal insulators. The loose structure of down feathers traps air.

As a result, energy cannot be transmitted easily through down feathers. This means birds are insulated from cold air outside, plus their body heat doesn't escape easily either.

Human beings discovered that down feathers are good for insulation long ago. For example, documents from the 1600s show that Russian merchants sold “bird down" to the Dutch hundreds of years ago.

Today, down is used in all sorts of products, including coats, bedding, and sleeping bags, to help better insulate the user from cold weather. Down can be collected from many different types of birds, but most of today's supply comes from domestic geese.

If you have a down coat or comforter, is it all down? In the United States, laws require that products labeled “100 percent down" contain only down feathers.

If your product is labeled “down," it can contain a mixture of both down feathers and synthetic fibers. Not all down feathers are created equal, though.

Down insulation is rated on a measure called “fill power." The higher the fill power, the more the down insulates.

The highest fill-power rating — 1200 — goes to eiderdown, which comes from the Common Eider duck. Eiderdown tends to be expensive.

3 0
3 years ago
A 1500 kg car traveling east at 40 km/hr turns a corner and speeds up to a velocity of 50 km/hr due north. What is the change in
pantera1 [17]

Answer:

96046  Ns.

Explanation:

We shall represent velocity in vector form considering east direction as + ve x axis and north as + y direction.

40 km/h in the east

V₁ = 40 i

V₂ = 50j

momentum p₁ = mV₁

= 1500 X 40 i

= 60000 i

Momentum p₂ = mV₂

= 1500 X 50j

= 75000 j

Change in momentum

p₂ - p₁

75000j - 60000i

Magnitude of change

= \sqrt{(750000)^2 +(60000)^2

= 96046  Ns.

5 0
3 years ago
Other questions:
  • Tala wants to create a sound echo. She can create the echo using a pane of glass or a carpet square. Which one does she choose?
    14·1 answer
  • Which three methods are valid for preventing further environmental damage from CO2?
    10·2 answers
  • . A chemistry student’s height is measured at 68.5 inches. How tall is the student in cm?
    9·2 answers
  • A metallic conductor has a resistivity of 35 × 10 −6 Ω⋅m. What is the resistance of a piece that is 20 m long and has a uniform
    6·1 answer
  • In 1974, the Arecibo Radio telescope in Puerto Rico was used to transmit a signal to M13, a star cluster about 25,000 light-year
    15·1 answer
  • A neutral metal ball is suspended by a string. A positively charged insulating rod is placed near the ball, which is observed to
    10·1 answer
  • (need help) " You make the following measurements of an object: 42kg and 22m^3. What would be the objects density be? Show work
    10·1 answer
  • 1. You are driving along a highway at 35.0 m/s when you hear the siren of a police car approaching you at 44.2 m/s from behind a
    11·1 answer
  • Describe how noise-cancelling headphones modify the sound waves around the user. Your answer should be three to four sentences i
    13·1 answer
  • What are some limitations to your direct observations of your environment? Give an example of an observation that could be made
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!