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34kurt
3 years ago
11

How many neutrons does element x have if it’s atomic number is 40 and it’s mass number is 82?

Physics
1 answer:
Black_prince [1.1K]3 years ago
4 0
The atomic number gives you the number of protons element x has. Since the mass of protons and neutrons are almost similar(around 1 amu), the mass number can be thought of as the sum of protons and neutrons. so if element x whose atomic number is 40 has a mass number of 82, then we know that 42 of those must be neutrons.
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What form of music has two parts and has two contrasting melodies? *
aleksandr82 [10.1K]

Answer: Ternary

Explanation: Ternary Form also has two parts, but is different from Binary Form. Relevance. Ternary form, sometimes called song form, is a three-part musical form where the first section (A) is repeated after the second section (B) ends. different words and same music.

Please mark as brainliest!

5 0
2 years ago
Find the equivalent resistance of this
frosja888 [35]

Answer:

Re=160ohm

Explanation:

Step#1

Rt=R1+R2 ( because both are in series)

Rt=(100+220 ) ohm

Rt=320 ohm

Step#2

Rt and R3 are parallel so,

Re= (Rt× R3) ÷ (Rt+R3)

Re= (320×320)÷( 320+320)

Re = 102,400÷ 640

Re=160ohm

7 0
3 years ago
A rock is thrown off a 50.0 m high cliff. How fast must the rock leave the cliff top to land on level ground below, 90 m from th
blagie [28]

Answer:

The rock must leave the cliff at a velocity of 28.2 m/s

Explanation:

The position vector of the rock at a time t can be calculated using the following equation:

r = (x0 + v0x · t, y0 + 1/2 · g · t²)

Where:

r = position vector at time t.

x0 = initial horizontal position.

v0x = initial horizontal velocity.

t = time.

g = acceleration due to gravity (-9.81 m/s² considering the upward direction as positive).

Please, see the attached figure for a graphical description of the problem. Notice that the origin of the frame of reference is located at the edge of the cliff so that x0 and y0 = 0.

When the rock reaches the ground, the position vector will be (see r1 in the figure):

r1 = (90 m, -50 m)

Then, using the equation of the vector position written above:

90 m = x0 + v0x · t

-50 m = y0 + 1/2 · g · t²

Since x0 and y0 = 0:

90 m = v0x · t

-50 m = 1/2 · g · t²

Let´s use the equation of the y-component of the vector r1 to find the time it takes the rock to reach the ground and with that time we can calculate v0x:

-50 m = 1/2 · g · t²

-50 m = -1/2 · 9.81 m/s² · t²

-50 m / -1/2 · 9.81 m/s² = t²

t = 3.19 s

Now, using the equation of the x-component of r1:

90 m = v0x · t

90 m = v0x · 3.19 s

v0x = 90 m / 3.19 s

v0x = 28.2 m/s

8 0
3 years ago
An AC adapter for a telephone answering machine uses a transformer to reduce the line voltage of 120 V to a voltage of 5.00 V. T
Maksim231197 [3]

Answer:

35

Explanation:

We are given that

Initial voltage,V_1=120 V

Final voltage, V_2=5 V

Number of tuns in primary coil of the transformer, N_p=840

Rms current, I_{rms}=580mA=580\times 10^{-3} A

1 mA=10^{-3} A

We have to find the number of turns  are there on the secondary coil.

We know that

\frac{N_s}{N_p}=\frac{V_2}{V_1}

Using the formula

\frac{N_s}{840}=\frac{5}{120}

N_s=\frac{5}{120}\times 840=35

Hence, there are  number of turns on the secondary coil=35

8 0
2 years ago
Light travels 3,00,000 km/s . Is it velocity or speed?​
Ludmilka [50]

Answer:

speed

Explanation:

according to your question, your answer is speed

7 0
2 years ago
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