What is the charge of an object with 14 electrons and 6 protons

Use the work—energy theorem to solve each of these problems. You can use Newton's laws to check your answers. Neglect air resist

andreyandreev [35.5K]

Answer:

a) It is moving at $43.15\frac{m}{s^{2}}$ when reaches the ground.

b) It is moving at $101.44\frac{m}{s^{2}}$ when reaches the ground.

Explanation:

Work energy theorem states that the total work on a body is equal its change in kinetic energy, this is:

$W=K_f-K_i$ (1)

with W the total work, Ki the initial kinetic energy and Kf the final kinetic energy. Kinetic energy is defined as:

$K=\frac{mv^2}{2}$ (2)

with m the mass and v the velocity.

Using (2) on (1):

$W=\frac{mv_f^2}{2}-\frac{mv_i^2}{2}$ (3)

In both cases the total work while the objects are in the air is the work gravity field does on them. Work is force times the displacement, so in our case is weight (w=mg) of the object times displacement (d):

$W=Fd=wd=mgd$ (4)

Using (4) on (3):

$mgd=\frac{mv_f^2}{2}-\frac{mv_i^2}{2}$ (5)

That's the equation we're going to use on a) and b).

a) Because the branch started form rest initial velocity (vi) is equal zero, using this and solving (5) for final velocity:

$v_f=\sqrt{\frac{2mgd}{m}}=\sqrt{2gd}=\sqrt{2*9.8*95}$

$v_f=43.15\frac{m}{s^{2}}$

b) In this case the final velocity of the boulder is instantly zero when it reaches its maximum height, another important thing to note is that in this case work is negative because weight is opposing boulder movement, so we should use -mgd:

$-mgd=-\frac{mv_i^2}{2}$

Solving for initial velocity (when the boulder left the volcano):

$v_i=\sqrt{\frac{2mgd}{m}}=\sqrt{2gd}=\sqrt{2*9.8*525}$

$v_i=101.44 \frac{m}{s^{2}}$

3 0

3 years ago

The speed of sound at room temperature (20 degrees Celsius) is 343 m/s. If the speed of sound in air increases about 0.60 m/s fo

stepan [7]

Answer:

36,67 degrees Celsius

Explanation:

The simplest way to approach this problem, given the information provided, is to simply start with the speed difference.

Goal: 353 m/s

Start: 343 m/s (at 20 degrees Celsius).

Difference: 10 m/s

Variation rate: 0.60 m/s/d (d = degree)

$d = \frac{10 m/s}{0.60 m/s/d} = 16,67 d$

So, 16,67 degrees more than the starting point.

The temperature will then be 36.67 degrees Celsius, when the sound travels at the speed of 353 m/s.

4 0

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What is the great red spot? what is the great red spot? a long-lived, high-pressure storm on jupiter a place where reddish parti

maxonik [38]

A long-lived, high-pressure storm on jupiter a place where reddish particles from io impact jupiter's surface

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Olivia is on a swing at the playground at which point is her kinetic energy increasing and her potential energy decreasing

Nimfa-mama [501]

Whenever an object is falling, its potential energy
is decreasing and its kinetic energy is increasing.

Olivia's potential energy is decreasing and her kinetic energy
is increasing as she moves toward the right side of the picture,
all the way from W, through X, to the bottom of the arc.

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The metal ions in iron are held together by

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Metals are giant structures of atoms held together by metallic bonds. “Giant” implies that large but variable numbers of Atoms are involved - depending on the size of the bits of metal. most metals are close packed - that is, they fit as many items as possible into the available volume.

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