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2 years ago

6

Two point charges, initially 3 cm apart, are moved to a distance of 1 cm apart. By what factor does the resulting electric force

between them change?
A. 3
B. 1/9
C. 1/3
D. 9

1 answer:

Solnce55 [7]2 years ago

6 0

The answer is B (1/9).

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What are the names of neptunes moons

alexandr402 [8]

Answer:

1. naiad

2.Thalassa

3 Despina

4 Galatea

5 Larissa

6 Hippocamp

7 Proteus ˈ

8 Triton

9 Nereid

10 Halimede

11 Sao

12 Laomedeia

13 Psamathe

14 Neso

Explanation:

hope this helped

5 0

3 years ago

Freight car A with a gross weight of 200,000 lbs is moving along the horizontal track in a switching yard at 4 mi/hr. Freight ca

zhenek [66]

Answer: a) 4.7 mi/hr. b) 86,500 lbs. mi²/Hr²

Explanation:

As in any collision, under the assumption that no external forces exist during the very small collision time, momentum must be conserved.

If the collision is fully inelastic, both masses continue coupled each other as a single mass, with a single speed.

So, we can write the following:

p₁ = p₂ ⇒m₁.v₁ + m₂.v₂ = (m₁ + m₂). vf

Replacing by the values, and solving for vf, we get:

vf = (200,000 lbs. 4 mi/hr + 100,000 lbs. 6 mi/hr) / 300,000 lbs = 4.7 mi/hr

If the track is horizontal, this means that thre is no change in gravitational potential energy, so any loss of energy must be kinetic energy.

Before the collision, the total kinetic energy of the system was the following:

K₁ = 1/2 (m₁.v₁² + m₂.v₂²) = 3,400,000 lbs. mi² / hr²

After the collision, total kinetic energy is as follows:

K₂ = 1/2 ((m₁ + m₂) vf²) = 3,313,500 lbs. mi²/hr²

So we have an Energy loss, equal to the difference between initial kinetic energy and final kinetic energy, as follows:

DE = K₁ - K₂ = 86,500 lbs. mi² / hr²

This loss is due to the impact, and is represented by the work done by friction forces (internal) during the impact.

8 0

3 years ago

Magnesium hydroxide is a common ___?

omeli [17]

Answer:

Magnesium hydroxide is the inorganic compound with the chemical formula Mg(OH)2. Magnesium hydroxide is a common component of antacids, such as milk of magnesia, as well as laxatives

Explanation:

pls mark brainliest

6 0

3 years ago

Read 2 more answers

You hold a metal block of mass 40 kg above your head at a height of 2 m.

Kitty [74]

Answer:

The work done by gravity is 784 J.

Explanation:

Given:

Mass of the block is, $m=40\ kg$

Height to which it is raised is, $h=2\ m$

Acceleration due to gravity is, $g=9.8\ m/s^2$

Now, work done by gravity is equal to the product of force of gravity and the distance moved in the direction of gravity. So,

$\textrm{Work by gravity}=F_g\times h$

Force of gravity is given as the product of mass and acceleration due to gravity.

$\therefore F_g=mg=40\times 9.8=392\ N$ . Now,

$\textrm{Work by gravity}=F_g\times h=392\times 2=784\ J$

Therefore, the work done by gravity is 784 J.

5 0

3 years ago

A 100 Kg man is diving off a 50 meter cliff. What is his kinetic energy when he is 20 meters from the water?

iren2701 [21]

Answer:

$K.E=29.403125J$

Explanation:

From the question we are told that

Mass $M=100$

Height $50-20=30m$

Generally the equation for velocity before impact is is is mathematically given by

$v=\sqrt{2gh}$

$v=\sqrt{2*9.8*30}$

$v=24.25$

Generally the equation for Kinetic Energy is is mathematically given by

$K.E=\frac{1}{2}mv^2$

$K.E=\frac{1}{2}*100*(24.25)^2\\$

$K.E=29403.125J$

$K.E=29.403125J$

8 0

3 years ago