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3 years ago

Later research indicated that electric current is actually the flow of ____

Physics

1 answer:

iren [92.7K]3 years ago

6 0

Answer:

Electrons.

Explanation:

Electricity was discovered before the discovery of electrons by J.J Thompson in 1896. Before the electron, it was thought that it is the positive ions that move through the wire and carry current—that's why today the conventional current represents the flow of positive charges.

After J.J Thompson's discovery of the electrons, it was realized that it is the electrons that actually carry the current through the conductor. But changing the direction of the conventional current didn't seem appropriate, and that's why the convention continues to be used to this day—reminding us that once it were the positive ions that were thought to carry the current.

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What is the equivalent resistance of a series circuit with the following resistors: 10 ohms, 35 ohms, and 150 ohms?

Eva8 [605]

Answer: R=10+35+150

R=195Ω

Explanation:

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3 years ago

Read 2 more answers

The center of a moon of mass m is a distance D from the center of a planet of mass M. At some distance x from the center of the

nataly862011 [7]

Answer with Explanation:

Let rest mass $m_0$ at point P at distance x from center of the planet, along a line connecting the centers of planet and the moon.

Mass of moon=m

Distance between the center of moon and center of planet=D

Mass of planet=M

We are given that net force on an object will be zero

a.We have to derive an expression for x in terms of m, M and D.

We know that gravitational force= $\frac{GmM}{r^2}$

Distance of P from moon=D-x

$F_m$ =Force applied on rest mass due to m

$F_m$ =Force on rest mass due to mas M

$F_M=F_m$ because net force is equal to 0.

$F_m=F_M$

$\frac{Gm_0m}{(D-x)^2}=\frac{Gm_0M}{x^2}$

$\frac{m}{(D-x)^2}=\frac{M}{x^2}$

$\frac{x^2}{(D-x)^2}=\frac{M}{m}$

$\frac{x}{D-x}=\sqrt{\frac{M}{m}}$

Let $R=\sqrt{\frac{M}{m}}$

Then, $\frac{x}{D-x}=R$

$x=DR-xR$

$x+xR=DR$

$x(1+R)=DR$

$x=\frac{DR}{1+R}$

b.We have to find the ratio R of the mass of the mass of the planet to the mass of the moon when x= $\frac{2}{3}D$

Net force is zero

$F_m=F_M$

$\frac{Gm_0m}{(D-\frac{2}{3}D)^2}=\frac{Gm_0M}{\frac{4}{9}D^2}$

$\frac{m}{\frac{D^2}{9}}=\frac{9M}{4D^2}$

$\frac{M}{m}=4$

Hence, the ratio R of the mass of the planet to the mass of the moon=4:1

8 0

4 years ago

Which two fields of study do the principles of biomechanics come from? A. science and technology B. physics and engineering C. b

kati45 [8]

Answer:

B. physics and engineering

Explanation:

Biomechanics is the study of mechanical laws and living organisms. Hence, it comprises of the interrelationships between physics and engineering.

8 0

3 years ago

A 0.140-kg baseball is dropped from rest from a height of 1.8 m above the ground. It rebounds to a height of 1.4 m. What change

aliina [53]

Answer:

$\Delta p=-1.56\ kg-m/s$

Explanation:

It is given that,

Mass of the baseball, m = 0.14 kg

It is dropped form a height of 1.8 m above the ground. Let u is the velocity when it hits the ground. Using the conservation of energy as :

$u=\sqrt{2gh}$

h = 1.8 m

$u=\sqrt{2\times 9.8\times 1.8}$

u = 5.93 m/s

Let v is the speed of the ball when it rebounds. Again using the conservation of energy to find it :

$v=\sqrt{2gh'}$

h' = 1.4 m

$v=-\sqrt{2\times 9.8\times 1.4}$

v = -5.23 m/s

The change in the momentum of the ball is given by :

$\Delta p=m(v-u)$

$\Delta p=0.14(-5.23-5.93)$

$\Delta p=-1.56\ kg-m/s$

So, the change in the ball's momentum occurs when the ball hits the ground is 1.56 kg-m/s. Hence, this is the required solution.

4 0

4 years ago

A 1.2-kg mass is projected from ground level with a velocity of 30 m/s at some unknown angle above the horizontal. A short time

Dmitriy789 [7]

Answer:

$K_f$ = 351.84 J

Explanation:

Using the conservation of energy K:

$E_i = E_f$

so:

$\frac{1}{2}mv^2 = K_f + mgh$

where m is the mass, v the initial velocity, $K_f$ is the kinetic energy of the mass as it clears the fence, g the gravity and h the altitude.

Then, replacing values, we get:

$\frac{1}{2}(1.2kg)(30m/s)^2 = K_f + (1.2kg)(9.8m/s^2)(16m)$

solving for $K_f$ :

$K_f$ = 351.84 J

3 0

3 years ago