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3 years ago

8

Define light yearend explain how and why light years are used to measure distances in the universe

1 answer:

yan [13]3 years ago

3 0

Light years are the distance light can travel in a full year. They are used because there are really big distances in the universe that are easier to measure with a really large form of measurement (light years).

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Amanda selects a sample of college students. She obtains the students' scores on several personality scales, as well as on a tes

andreyandreev [35.5K]

Answer:

descriptive

Explanation:

In this scenario, Amanda would use descriptive statistics in order to present the raw data. That is because, this type of statistic fulfills her goal of summarizing the raw data, while still providing clear and accurate quantitative analysis regarding the different features of the study through the different tests done. Including the personality scales and creativity test data. Since this provides such information it would best fit the goal of what Amanda is trying to accomplish.

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3 years ago

What type of rock converts into over rock types under different conditions

Tasya [4]

Answer:

the metamorphic rock converts into other rock types under different conditions

4 0

3 years ago

Why is your State have dimensions

Ilya [14]

Answer:

not sure you

Explanation:

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4 years ago

A small laser used as a pointer produces a beam of red light 5 mm in diameter, and has a power output of 5 milliwatts. What is t

Nata [24]

Answer:

434.0 V/m

Explanation:

The power output of the laser is:

$P=5 mW = 0.005 W$

while the radius of the beam is

$r=\frac{5 mm}{2}=2.5 mm = 0.0025 m$

so the cross-sectional area is

$A=\pi r^2 = \pi (0.0025 m)^2=2.0\cdot 10^{-5} m^2$

So the intensity of the laser beam is

$I=\frac{P}{A}=\frac{0.005 W}{2.0\cdot 10^{-5} m^2}=250 W/m^2$

The intensity of a laser beam is related to the magnitude of the electric field by

$I=\frac{1}{2}c\epsilon_0 E^2$

where

c is the speed of light

$\epsilon_0$ is the vacuum permittivity

Solving the formula for E, we find

$E=\sqrt{\frac{2I}{c\epsilon_0}}=\sqrt{\frac{2(250 W/m^2)}{(3\cdot 10^8 m/s)(8.85\cdot 10^{-12} F/m)}}=434.0 V/m$

4 0

3 years ago

Suppose a skydiver (mass=75kg) is falling toward the earth when the skydiver is 100m above the earth he is moving at 60m/s at th

IRISSAK [1]

Given:

Mass(m)=75kg

Height (h) =100m

v(velocity)=60m/s

a(g)=9.8m/s^2(since it is a free falling object)

Now we know that

v=u+at

We know that

Potential energy=mgh

Where m is the mass

g is the acceleration due to gravity

h is the height above the ground

Substituting the above values we get

Potential energy=75 x 9.8 x 100

=73500N

Now kinetic energy =1/2mv^2

Where m is the mass

v is the velocity

Kinetic energy= 1/2 (75x60 x 60)

Kinetic energy=135000N

Now mechanical energy=

Kinetic energy+ Potential energy

Substituting the values in the above formula we get

Mechanical energy= 73500+135000

=208500N

7 0

4 years ago

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