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3 years ago

The mass number of a neutral atom of potassium (z=19) is 40 How many electrons does it have?

Physics

1 answer:

BlackZzzverrR [31]3 years ago

7 0

Answer:

Explanation:

Two

The nuclear force does not work

under long distances

is greater in strength the the electomagnetic force when the distances are small.

I'm not sure what D means.

I think it does depend on charge.

You have to choose D but this is a notes question and I'm not at all certain of the answer.

One

If its number is 19, the the number of protons = the number of electrons = 19

Answer B

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11. A plow pushes 100 kg of snow with 300 N of force. How much is the pile of snow accelerated?

Fed [463]

Answer:

Explanation:

This is an application of Newton's second Law.

Formula

F = m * a

F = 300 N

m = 100 kg

a = ?

F = m * a

300N = 100 kg * a Divide by 100

300N/100kg = a

a = 3 m/sec^2

3 0

2 years ago

An object is projected from the ground with an upward speed of ų m/s has a speed of 23m/s when it is at a height of 5m above the

vovikov84 [41]

Answer:

25.08m/s

Explanation:

mgh1 + 0.5mv1² = mgh2 + 0.5mv2²

h1 = 0m

v1 = u

h2 = 5m

v2 = 23m/s

putting the values into the formula above;

m(10)(0) + 0.5m(u²) = m(10)(5) + 0.5m(23²)

0 + 0.5mu² = 50m + 264.5m

0.5mu² = 314.5m

dividing through by m

0.5u² = 314.5

u² = 629

u = 25.08m/s

Therefore, the initial speed "u" = 25m/s

6 0

3 years ago

Which of the following best illustrates Lewin's interactionist perspective?

expeople1 [14]

Answer:

The options are

a. Sally is a very creative kind of person who likes to build things.

b. Jerry only works because he receives a very large income.

c. Rikki is usually shy, but at work she appears to be quite outgoing.

d. Maury gives money to charities because he wants other people to think he is very generous.

The answer is c. Rikki is usually shy, but at work she appears to be quite outgoing.

Lewin's interactionist perspective explains that an individual’s behavior is usually dependent on his personal behavior/ trait and the environment. The best option is that Rikki is usually shy which is her personal behavior but at work she appears to be quite outgoing due to her environment.

8 0

3 years ago

A hydrogen atom in a galaxy moving with a speed of 6.65×106 m/???? away from the Earth emits light with a wavelength of 5.13×10−

Mumz [18]

Answer:

The observed wavelength on Earth from that hydrogen atom is $5.24\times 10^{-7}\ m$ .

Explanation:

Given that,

The actual wavelength of the hydrogen atom, $\lambda_a=5.13\times 10^{-7}\ m$

A hydrogen atom in a galaxy moving with a speed of, $v=6.65\times 10^6\ m/s$

We need to find the observed wavelength on Earth from that hydrogen atom. The speed of galaxy is given by :

$v=c\times \dfrac{\lambda_o-\lambda_a}{\lambda_a}$

$\lambda_o$ is the observed wavelength

$\lambda_o=\dfrac{v\lambda_a}{c}+\lambda_a\\\\\lambda_o=\dfrac{6.65\times 10^6\times 5.13\times 10^{-7}}{3\times 10^8}+5.13\times 10^{-7}\\\\\lambda_o=5.24\times 10^{-7}\ m$

So, the observed wavelength on Earth from that hydrogen atom is $5.24\times 10^{-7}\ m$ . Hence, this is the required solution.

8 0

3 years ago

The isotope of an atom containing 31 protons and 39 neutrons suddenly has two neutrons added to it. What isotope is created?

Over [174]

It's the second one I hope I'm right

4 0

3 years ago

Read 2 more answers