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3 years ago

What happens to the kinetic energy of a snowball as it rolls across the lawn and gains mass?

1 answer:

8 0

Well, there's a lot of friction going on there, so the snowball gradually
loses kinetic energy just from bouncing and plowing through the snow
on the ground.

But I don't think you're asking about that. I think you're ignoring that
for the moment, and asking how its kinetic energy changes as its
mass increases. We know that

Kinetic Energy = (1/2) (mass) (speed²)

and THAT seems to say that more mass means more kinetic energy.
So maybe the snowball's kinetic energy increases as it picks up
more mass.

Don't you believe it !

Remember: Energy always has to come from somewhere ... a motor,
a jet, a push, gravity ... something ! It doesn't just appear out of thin air.
If the snowball were rolling down hill, then it could get more kinetic energy
from gravity. But if it's rolling on level ground, then it can never have any
more kinetic energy than you gave it when you pushed it and let it go.

If snow or leaves stick to it and its mass increases, then its speed must
decrease, in order to keep the same kinetic energy.

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This is what occurs when matter transitions between solid, liquid and gas.

vodomira [7]

Answer:

The answer is Phase Change

Explanation:

4 0

3 years ago

Read 2 more answers

4) (5 points) Given are the magnitudes and orientations (with respect to x-axis) of 3

Kazeer [188]

Expand each vector into their component forms:

$\vec A=(4.5\,\mathrm N)(\cos\theta_A\,\vec\imath+\sin\theta_A\,\vec\jmath)=(2.58\,\vec\imath+3.69\,\vec\jmath)\,\mathrm N$

Similarly,

$\vec B=(-1.23\,\vec\imath+0.860\,\vec\jmath)\,\mathrm N$

$\vec C=(-3.44\,\vec\imath-4.91\,\vec\jmath)\,\mathrm N$

Then assuming the resultant vector $\vec R$ is the sum of these three vectors, we have

$\vec R=\vec A+\vec B+\vec C$

$\vec R=(-2.09\,\vec\imath-0.368\,\vec\jmath)\,\mathrm N$

and so $\vec R$ has magnitude

$\|\vec R\|=\sqrt{(-2.09)^2+(-0.368)^2}\,\mathrm N\approx2.12\,\mathrm N$

and direction $\theta_R$ such that

$\tan\theta_R=\dfrac{-0.368}{-2.09}\implies\theta_R=-170^\circ=190^\circ$

5 0

3 years ago

A lens collects light and focuses it into a small spot. This increases the ________ of the light wave.A lens collects light and

Anika [276]

Answer:

intensity.

Explanation:

when the light collected by the lens is focused into a small spot it tends to increase the intensity of the light.

as different path of light with different intensity combines from passing through the lens it tends to make the light path and intensity coherent and after being coherent there intensity increases.

8 0

3 years ago

Which law is used to find the magnitude of a magnetic force?

Talja [164]

Answer:

The Flemings left hand rule is used to find the magnitude of a magnetic force

Explanation:

Fleming's left hand rule states that if the first three fingers are held mutually at right angles to one another, then the fore finger points into the direction of magnetic field the middle finger in the direction of current while the thumb points in the direction of force.

Mathematically

Magnetic Force F= BILsinθ

Where

B= magnetic field density Tesla

I= current

L= length of conductor

θ= angle of conductor with field

3 0

3 years ago

The amount of water vapor in the air is known as the

WITCHER [35]

It is know as smoke because if you cook food smoke will go up in the air and that makes vapor and also water from the ground it suck up

5 0

3 years ago