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4 years ago

The first nucleus of an atom was shown as?

Physics

2 answers:

postnew [5]4 years ago

6 0

<h2>Answer: A solid mass</h2>

The first atomic model was the one proposed by Jhon Dalton, according to which it is postulated that:

"Matter is made up of indivisible, indestructible and extremely small particles called atoms."

That is, the atom is a solid and indivisible mass.

However, over time some limitations were found in Dalton's atomic model and was replaced by the Thomson's atomic model, then by Rutherford's, Bohr's, Sommerfield's, and finally Shrodinger's.

Currently it is known that each atom is composed of a nucleus and one or more electrons attached to the nucleus, which is composed of one or more protons and typically a similar number of neutrons.

In addition, the atomic nucleus is the central part of the atom and concentrates most of the total mass of the atom.

Therefore, the correct option is A.

Sveta_85 [38]4 years ago

6 0

Answer:

A solid mass

Explanation:

took test

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A circular conducting loop with a radius of 0.50 m and a small gap filled with a 10.0-Ω resistor is oriented in the xy-plane. If

saul85 [17]

Answer:

Current, I = 0.153 A

Explanation:

Given that,

Radius of the circular conducting loop, r = 0.5 m

Resistance of the resistor, $R=10\ \Omega$

Magnetic field, B = 1 T

Angle with z axis, $\theta=30^{\circ}$

Magnetic field increases to 10 T in 4 seconds

To find,

Magnitude of current.

Solve,

According to Faraday's law, the induced emf is given by:

$\epsilon=\dfrac{\phi_f-\phi_i}{t}$

$\phi_f\ and\ \phi_i$ are final flux and the initial flux respectively.

$\epsilon=NA\ cos\theta\dfrac{B_f-B_i}{t}$

$\epsilon=1\times \pi (0.5)^2\ cos(30)\dfrac{10-1}{4}$

$\epsilon=1.53\ V$

The magnitude of current can be calculated using the Ohm's law as :

$I=\dfrac{\epsilon}{R}$

$I=\dfrac{1.53}{10}$

I = 0.153 A

Therefore, the magnitude of the current that will be caused to flow in the loop is 0.153 A.

3 0

4 years ago

An airplane accelerates from a speed of 88m/s to a speed of 132 m/s during a 15 second time interval. How far did the airplane t

Gelneren [198K]

Answer:

$1650\:\mathrm{m}$

Explanation:

We can use the following kinematics equations to solve this problem:

$v_f=v_i+at,\\{v_f}^2={v_i}^2+2a\Delta x$ .

Using the first one to solve for acceleration:

$132=88+a(15),\\15a=44,\\a=\frac{44}{15}=2.9\bar{3}\:\mathrm{m/s^2}$ .

Now we can use the second equation to solve for the distance travelled by the airplane:

$132^2=88^2+2\cdot2.9\bar{3}\cdot \Delta x,\\\Delta x= \frac{9680}{2\cdot2.9\bar{3}},\\\Delta x =\fbox{$ 1650\:\mathrm{m}$}$ (three significant figures).

6 0

3 years ago

An aircraft travels a distance of 50km in a straight line

Juliette [100K]

Answer:

200 m/s

Explanation:

v = distance / time = 50km/250s = 50000m/250s = 200 m/s

6 0

3 years ago

A satellite that weighs 4900 N on the launchpad travels around the earth's equator in a circular orbit with a period of 1.667 h.

charle [14.2K]

Answer:

(a)F= 3.83 * 10^3 N

(b)Altitude=8.20 * 10^5 m

Explanation:

On the launchpad weight = gravitational force between earth and satellite.

W = GMm/R²

where R is the earth radius.

Re-arranging:

WR² / GM = m

m = 4900 * (6.3 * 10^6)² / (6.67 * 10^-11 * 5.97 * 10^24) = 488 kg

The centripetal force (Fc) needed to keep the satellite moving in a circular orbit of radius (r) is:

Fc = mω²r

where ω is the angular velocity in radians/second. The satellite completes 1 revolution, which is 2π radians, in 1.667 hours.

ω = 2π / (1.667 * 60 * 60) = 1.05 * 10^-3 rad/s

When the satellite is in orbit at a distance (r) from the CENTRE of the earth, Fc is provided by the gravitational force between the earth and the satellite:

Fc = GMm/r²

mω²r = GMm / r²

ω²r = GM / r²

r³ = GM/ω² = (6.67 * 10^-11 * 5.97 * 10^24) / (1.05 * 10^-3)²

r³ = 3.612 * 10^20

r = 7.12 * 10^6 m

(a) F = GMm/r²

F=(6.67 * 10^-11 * 5.97 * 10^24 * 488) / (7.12 * 10^6 )²

F= 3.83 * 10^3 N

(b) Altitude = r - R = (7.12 * 10^6) - (6.3 * 10^6) = 8.20 * 10^5 m

4 0

3 years ago

a motorcyclist starts from rest and accelerates at rate of 4 meters per second squared north. what is the final velocity of the

MArishka [77]

Answer:

80m/s

Explanation:

Final velocity is given by

v=u+at

when a motorcyclist starts from rest, initial velocity (u) =0

therefore

v=0+4*20

v=80m/s

that's the answer

8 0

4 years ago