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
Anna35 [415]
3 years ago
11

All atoms of the element potassium have 19 protons. One of the most stable types of potassium atoms has the mass number 39. How

many neutrons make up one of these potassium atoms? 19 20 38 58
Physics
2 answers:
Deffense [45]3 years ago
4 0

The correct answer is 20 neutrons

ozzi3 years ago
3 0
The formular for determinatio of mass number is this:
Mass number = number of proton + number of neutron
From the question, we are told that:
Mass number = 39
Proton number = 19
Number of proton = ?
Number of neutron = mass number -  number of proton
Number of neutron= 39 - 19 = 20
Therefore, number of neurtron = 20. 
You might be interested in
A small sandbag is dropped from rest from a hovering hot-air balloon. (assume the positive direction is upward.) (a) after 1.5 s
marishachu [46]

solution:

We know v0 = 0, a = 9.8, t = 4.0. We need to solve for v

so,

we use the equation:

v = v0 + at

v = 0 + 9.8*4.0

v = 39.2 m/s

Now we just need to solve for d, so we use the equation:

d = v0t + 1/2*a*t^2

d = 0*4.0 + 1/2*9.8*4.0^2

d = 78.4 m

3 0
3 years ago
Convert 800 cm to meters.
Rasek [7]

Answer:8 meters

Explanation:100cm is a meter

8 0
2 years ago
Read 2 more answers
Why do elements within a group have similar chemical properties
CaHeK987 [17]
Elements<span> in the same </span>group<span> in the periodic table </span>have similar chemical properties<span>. This is because their atoms </span>have<span> the same number of electrons in the highest occupied energy level. </span>Group<span> 1 </span>elements<span> are reactive metals called the alkali metals.</span>Group<span> 0 </span>elements<span> are unreactive non-metals called the noble gases.
</span>
4 0
3 years ago
Is language an innate or an acquired one
horsena [70]
It's acquired. Innate means you have it at birth, acquired means you picked it up. Obviously babies can't speak ;) so it's acquired.
3 0
2 years ago
Two blocks with masses 1 and 2 are connected by a massless string that passes over a massless pulley as shown. 1 has a mass of 2
Bess [88]

Answer:

The acceleration of M_2 is  a =  0.7156 m/s^2

Explanation:

From the question we are told that

    The mass of first block is  M_1 =  2.25 \ kg

    The angle of inclination of first block is  \theta _1 =  43.5^o

    The coefficient of kinetic friction of the first block is  \mu_1  = 0.205

      The mass of the second block is  M_2 = 5.45 \ kg

     The angle of inclination of the second block is  \theta _2 =  32.5^o

      The coefficient of kinetic friction of the second block is \mu _2 = 0.105

The acceleration of M_1 \ and\  M_2 are same

The force acting on the mass M_1 is mathematically represented as

     F_1 = T -  M_1gsin \theta_1 - \mu_1 M_1 g cos\theta_1

=> M_1 a = T -  M_1gsin \theta_1 - \mu_1 M_1 g cos\theta_1

Where T is the tension on the rope

The force acting on the mass M_2 is mathematically represented as    

  F_2 =  M_2gsin \theta_2 - T -\mu_2 M_2 g cos\theta_2

   M_2 a =  M_2gsin \theta_2 - T -\mu_2 M_2 g cos\theta_2

At equilibrium

  F_1 =  F_2

So

 T -  M_1gsin \theta_1 - \mu_1 M_1 g cos\theta_1 =M_2gsin \theta_2 - T -\mu_2 M_2 g cos\theta_2

making a the subject of the formula

    a =  \frac{M_2 g sin \theta_2 - M_1 g sin \theta_1 - \mu_1 M_1g cos \theta - \mu_2 M_2 g cos \theta_2 }{M_1 +M_2}

substituting values a =  \frac{(5.45) (9.8) sin (32.5) - (2.25) (9.8) sin (43.5) - (0.205)*(2.25) *9.8cos (43.5) - (0.105)*(5.45) *(9.8) cos(32.5) }{2.25 +5.45}

    => a =  0.7156 m/s^2

     

3 0
3 years ago
Other questions:
  • Adam takes a bus on a school field trip. The bus route is split into the five legs listed in the table. Find the average velocit
    10·1 answer
  • When all parts of a circuit are composed of conducting materials, the circuit is said to be
    6·1 answer
  • What does each of the facts shown above tell you about the element
    14·1 answer
  • In an out of control ceramics workshop, two clay balls collide in mid air and stick together. the first has mass 3.1 kg and coll
    7·1 answer
  • What is a substance?
    8·1 answer
  • Objects fall at constant velocity
    12·2 answers
  • HELP ASAP REAL ANSWERS PLEASE You push a box across the floor with a force of 30 N. You push it 15 meters in 8 seconds. How much
    5·2 answers
  • Write one to two sentences explaining whether this passage from the story is exposition, rising action, climax, or resolution: “
    9·2 answers
  • The energy diagram shows the changes in energy during a chemical reaction.
    7·1 answer
  • Model a hydrogen atom as a three-dimensional potential well with Uo = 0 in the region 0 &lt; x a. 283 eV <br> b. 339 eV <br> c.
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!