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4 years ago

What parts of an atom determines which element it is?

Physics

2 answers:

lara [203]4 years ago

5 0

Answer: Protons determine which element the atom is. (also known as the atomic number)

uysha [10]4 years ago

4 0

Explanation:

The protons determines the atomic number which helps in identifying an atom of an element

You might be interested in

Why am i getting so many spam calls on my cell phone.

OleMash [197]

Answer:

Why do I keep getting spam calls? Experts credit the ascendance of spam phone calls to fundamental problems with caller ID, a phone system where anyone can operate as a carrier, the inability to detect bad callers, and a number of bad actors exploiting those flaws to drive billions of calls to American phones.

Explanation:

5 0

2 years ago

1. Is the collision between the ball and the pendulum elastic or inelastic? Justify your answer by calculating the kinetic energ

Nitella [24]

Answer:

So energy is not conserved and inelastic shock

Explanation:

In the collision between a bullet and a ballistic pendulum, characterized in that the bullet is embedded in the block, if the kinetic energy is conserved the shock is elastic and if it is not inelastic.

Let's find the kinetic energy just before the crash

K₀ = ½ m vₓ₀²

After the crash we can use the law of conservation of energy

Starting point. Right after the crash, before starting to climb

Em₀ = K = ½ (m + M) v₂²

Final point. At the maximum height of the pendulum

$Em_{f}$ = U = (m + M) g h

Where m is the mass of the bullet and M is the mass of the pendulum

Em₀ = Em_{f}

½ (m + M) v₂² = (m + M) g h

v₂ = √ 2g h

Now we can calculate the final kinetic energy

K_{f} = ½ (m + M) v₂²²

K_{f} = ½ (m + M) (2gh)

The relationship between these two kinetic energies is

K₀ / K_{f} = ½ m vₓ₀² / (½ (m + M) 2 g h)

K₀ / K_{f} = m / (m + M) vₓ₀² / 2 g h

We can see that in this relationship the Ko> Kf

So energy is not conserved and inelastic shock

5 0

4 years ago

Suppose all the people of the Earth go to the North Pole and, on a signal, all jump straight up. Estimate the recoil speed of th

Makovka662 [10]

Explanation:

It is known that relation between velocity and height is as follows.

v = $\sqrt{2gh}$

where, g = acceleration due to gravity = 9.8 $m/s^{2}$

h = height = 0.2 m

Therefore, velocity is calculated as follows.

v = $\sqrt{2gh}$

= $\sqrt{2 \times 9.8 \times 0.2}$

= 3.92 m/s

Also,

$m_{people}v_{people} = m_{earth}v_{earth}$

$v_{earth} = \frac{m_{people}v_{people}}{m_{earth}}$

Putting the given values into the above formula as follows.

$v_{earth} = \frac{m_{people}v_{people}}{m_{earth}}$

= $\frac{6 \times 10^{9} \times 74 kg/person}{6 \times 10^{24} kg}$

= $\frac{444 \times 10^{9}}{6 \times 10^{24}}$

= $74 \times 10^{-15}$ m/s

or, = $7.4 \times 10^{-14}$ m/s

Thus, we can conclude that recoil speed of the Earth is $7.4 \times 10^{-14}$ m/s.

4 0

3 years ago

Consider an electron, of charge magnitude e = 1.602 10-19 C and mass me = 9.11 10-31 kg, moving in an electric field with an ele

Tems11 [23]

Answer: v= 7.509 x 10^6 m/s

B) the lower plate because the electron is negatively charged

Explanation:

From the question

Electronic charge (q) =1.602 x 10^-19c

Electric field intensity (E) = 8 x 10² = 800N/C

Mass of electron (m) = 9.11 x 10^-31 kg

Length of plate (L) = 50cm=0.5m

Distance between plates (D) = 20cm = 0.2m

Since the electron is entering a uniform electric field, the resulting motion will be of a constant acceleration and can be defined by the equations of motion with a constant acceleration.

From newton's law of motion.

F= ma

The force (F) is coming from the electric field which is

F=Eq.

Thus F = 800 x 1.602 x 10^-19

F = 1.2816 x 10^-16 N

Acceleration of electron (a) = F/m where m is the mass of electron (given above)

Hence

a = 1.2816 x 10^-16 / 9.11 x 10^-31

a= 1.41 x 10¹⁴ m/s².

Using Newton laws of motion to get velocity, we recall that v²= u² + 2ad

Where v is final velocity, u is initial velocity (zero in this case because the electron starts it motion from rest), a= acceleration, d= distance traveled (which in this case is distance between plates)

v² = 0² + 2(1.41 x 10¹⁴) x 0.2

v² = 5.64 x 10¹³

Thus v = √ 5.64 x 10¹³

v = 7.509 x 10^6 m/s

Since the electric field is upwards it denotes that the positive plate is downward and the negative is upward ( this is because electric flux from a positive charge has an outward flow and that from a negative charge has an inward flow. So from our questions, if the electric field is upward, it means it is starting from the bottom plate which will be positive) the electron (which is negatively charged) will be attracted to the positive plate which is downward for this question of ours.

So therefore, the electron is attracted to the downward plate because it (electron) is negative

Option B

4 0

4 years ago

A block of mass m is at rest at the origin at t=0. It is pushed with constant force F0 from x=0 to x=Lacross a horizontal surfac

Tomtit [17]

Answer:

A) v = √[(F₀/m - μ₀) 2x + x2 / L] , b) v = √[2 (F₀ / m - μ₀) +1] L

Explanation:

For this exercise we will use Newton's second law

X axis

Fo - fr = ma

Y Axis

N - W = 0

N = mg

The equation for the force of friction is

fr = μ N

.fr = μ mg

Let's replace

Fo - μ mg = m a

a = Fo / m - μ g

They ask us the speed of the block, so we must use

a = dv / dt = dv/dx dx dt = dv/dx v

v dv = a dx

We replace

v dv = (F₀ / m - μ₀ (1- x/L)) dx

We integrate

∫v dv = F₀ / m ∫ dx - μ₀ ∫ dx + 1 / L ∫ x dx

½ v² = (F₀ / m - μ₀) x + 1 / L x² / 2

We evaluate from the lower limit, for x = 0 the speed is zero v = 0, to the upper limit x, v

½ v² = (F₀ / m - μ₀) x + 1 / 2L x²

v = √[(F₀ / m - μ₀) 2x + x2 / L]

Part B

The velocity for x = L

v = √(F₀ / m - μ₀) 2L + L2 / L

v = √[2 (F₀ / m - μ₀) +1] L

8 0

3 years ago