1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Zolol [24]
3 years ago
11

Humans obtain energy in a number of different ways. About half of the electrical energy in the U.S. is generated by burning coal

, largely because coal is very inexpensive. But some electrical energy is generated by capturing sunlight with solar panels.
Which of these is a reason why many people want to use more solar panels and less coal?

A.
Coal is a renewable resource, while sunlight is a nonrenewable resource.
B.
Coal is more abundant than sunlight.
C.
Burning coal tends to harm the environment more than using solar panels.
D.
Coal energy is cleaner than solar energy.
Physics
1 answer:
ivanzaharov [21]3 years ago
6 0

Answer:

C. Burning coal tends to harm the environment more than using solar panels.

Explanation:

When coal is burned, it reacts with the oxygen in the air. This reaction converts the stored potential energy, which turns into thermal energy, which is released as heat. But it also produces methane and carbon dioxide which is released into the air.

You might be interested in
If a car travels 600m west in 25 seconds, what is its velocity?
Elena L [17]

v =  \frac{ \:the covered distance}{time} \\

v =  \frac{600}{25} =  \frac{6 \times 100}{25} = 6 \times 4 = 24 \:  \\

v = 24 \:  \frac{m}{s} \\

_________________________________

If west means the west of the axis x the velocity equal :

- 24 \:  \frac{m}{s} \\

4 0
3 years ago
You toss a rock up vertically at an initial speed of 39 feet per second and release it at an initial height of 6 feet. The rock
3241004551 [841]

Answer:

2.583 s, 29.77 ft and 1.219 s

Explanation:

Using equation of motion and taken the motion upward as positive, also a = g ( acceleration due to gravity) = - 32 fts⁻², V= 39 fts⁻¹ V₁ is final velocity, y is the distance in ft from the ground

H = 6 ft, the height from which it is tossed

V₁ = V + gt = V - gt

at maximum height the body came to rest momentarily V₁ = 0

0 = V - gt

-V = -gt

- 39 / -32 = t

t time to reach maximum height = 1.219 s

To Maximum height reached can be calculated with the formula

V₁² = V² + 2g( y - H) where H is the initial height reached by the tossed rock

where V₁ is the final velocity at maximum height which = 0

0 = V² - 2g(y-H) where y is the distance traveled from the ground

-V² = -2g(y-H)

₋V² / -2g = y-H

(V²/2g) + H = y in ft

(39² / (2 × 32)) + 6

y = 29.77 ft

The total time it will be in air can be calculated with the formula below

y = H + Vt - 0.5gt² from y-H = ut + 0.5at²

0.5gt² - Vt - H = 0 since the body returned to the ground ( y = 0)

0.5gt² - Vt - H = 0

using quadratic formula

- (-V)² ± √ ((-V²) - 4 × 0.5g × -H) / (2 × 0.5 × g)

(V ± √ (V² + 2gH)) ÷ g

substitute the values into the expression

t = (39 + √(39² + (2×-32× 6)))/ 32 or (39 - √ (39² + (2 × -32×6))/ 32

t = (39 + √(1521 +384))/32 = (39 + √1905) / 32  = 2.583 s

t = (39 - √1905) / 32 =  -0.15 s

The will remain in air (V ± √ (V² + 2gH)) / g seconds. It will reach a maximum height of (V²/2g) + H feet after V/g seconds

8 0
2 years ago
A car moving at a speed of 36 km/h reaches the foot of a smooth
boyakko [2]

Answer:

d = 10.2 m

Explanation:

When the car travels up the inclined plane, its kinetic energy will be used to do the work in climbing up. So according to the law of conservation of energy, we can write that:

Kinetic\ Energy\ of\ the \ Car = Work\ Done\ while\ moving\ up\ the\ plane\\\frac{1}{2}mv^{2} = Fd

where,

m = mass of car

v = speed of car at the start of plane = (36 km/h)(1000 m/1 km)(1 h/3600 s)

v = 10 m/s

F = force on the car in direction of inclination = W Sin θ

W = weight of car = mg

θ = Angle of inclinition = 30°

d = distance covered up the ramp = ?

Therefore,

\frac{1}{2}mv^{2} = mgdSin\theta\\\frac{1}{2}v^{2} = gdSin\theta\\\frac{1}{2}(10\ m/s)^{2} = d(9.81\ m/s^{2}) Sin\ 30^{0}

<u>d = 10.2 m</u>

4 0
2 years ago
What type of cloud is made up of both liquid water droplets &amp; ice crystals
andre [41]

Answer: Altostratus clouds they are gray or blue gray mid level clouds.

Explanation:

7 0
1 year ago
The objective lens of a microscope has a focal length of 5.5mm. Part A What eyepiece focal length will give the microscope an ov
son4ous [18]

Complete Question

The distance between the objective and eyepiece lenses in a microscope is 19 cm . The objective lens has a focal length of 5.5 mm .

What eyepiece focal length will give the microscope an overall angular magnification of 300?

Answer:

The  eyepiece focal length is  f_e  = 0.027 \ m

Explanation:

From the question we are told that

    The focal length is  f_o =  5.5 \ mm =  -0.0055 \ m

This negative sign shows the the microscope is diverging light

     The  angular magnification is m = 300

     The  distance between the objective and the eyepieces lenses is  Z =  19 \ cm  = 0.19 \ m

Generally the magnification is mathematically represented as

        m  =  [\frac{Z - f_e }{f_e}] [\frac{0.25}{f_0} ]

Where f_e is the eyepiece focal length of the microscope

  Now  making f_e the subject  of the formula

         f_e  = \frac{Z}{1 - [\frac{M  *  f_o }{0.25}] }

substituting values

        f_e  = \frac{ 0.19 }{1 - [\frac{300  *  -0.0055 }{0.25}] }

         f_e  = 0.027 \ m

     

5 0
2 years ago
Other questions:
  • Displacement vectors of 3 m and 5 m in the same direction combine to make a displacement vector that is _____ in magnitude.
    15·2 answers
  • How large an expansion gap should be left between steel railroad rails if they may reach a maximum temperature 36.0°C greater th
    15·1 answer
  • 16. An object has a mass of 13.5 kilograms. What force is required to accelerate it to a rate of 9.5 m/s2?
    8·2 answers
  • If you weigh 660 N on the earth, what would be your weight on the surface of a neutron star that has the same mass as our sun an
    12·1 answer
  • Optical tweezers use light from a laser to move single atoms and molecules around. Suppose the intensity of light from the tweez
    6·1 answer
  • A parallel-plate air capacitor with a capacitance of 260 pF has a charge of magnitude 0.155 μC on each plate. The plates have a
    13·1 answer
  • What is the difference between an observation and an inference?
    7·1 answer
  • All of the following are kinds of forces except thrust acceleration gravity friction
    6·1 answer
  • Do you think a moving skateboard has energy? Why or Why not? What about a skateboard that is not moving?
    10·2 answers
  • What is a key phrase for remembering the order of the planets?
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!