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
Harman [31]
3 years ago
15

What percentage of the world's energy needs is supplied by fossil fuels?

Physics
1 answer:
bagirrra123 [75]3 years ago
5 0
13.4 %

Hope this helped
You might be interested in
Which of the following metals require ultraviolet light to exhibit the photoelectric effect?The options available: a. Cs, work f
Eddi Din [679]

Answer:

b. AG, work function=4.74eV

Explanation:

Ultraviolet light starts at the end of the visible light spectrum, where violet light ends:

\lambda=380 nm =3.8\cdot 10^{-7}m (wavelength of lowest-energy ultraviolet light)

So, the lowest energy of ultraviolet light can be found by using the formula

E=\frac{hc}{\lambda}

where

h is the Planck constant

c is the speed of light

Substituting,

E=\frac{(6.63\cdot 10^{-34} Js)(3\cdot 10^8 m/s)}{3.8\cdot 10^{-7} m}=5.23\cdot 10^{-19}J

And keeping in mind that

1 eV = 1.6\cdot 10^{-19}J

This energy converted into electronvolts is

E=\frac{5.23\cdot 10^{-19} J}{1.6\cdot 10^{-19} J/eV}=3.27 eV

The work function of a metal is the minimum energy needed to extract a photoelectron from the surface of the metal. Therefore, the metals that exhibit photoelectric effect are the ones whose work function is larger than the energy we found previously, so:

b. AG, work function=4.74eV

Because for all the other metals, visible light will be enough to extract photoelectrons.

7 0
3 years ago
The strength of force is expressed by a. Weight b.mass
HACTEHA [7]

Answer:

Weight.

Explanation:

4 0
3 years ago
Two long, parallel wires carry currents of different magnitudes. if the amount of current in each wire is doubled, what happens
Mrac [35]
The force per unit of length between two wires carrying current is
\frac{F}{L}= \frac{\mu_0 I_1 I_2}{2 \pi r}
where I1 and I2 are the currents in the two wires, while r is the distance between them.

We can see from the formula that the force is proportional to the product between I1 and I2: F \sim I_1 I_2
so, if we double both I1 and I2, we get a factor 4:
F' \sim (2I_1 )(2I_2)=4 I_1 I_2 =4 F
so, the force between the wires will be 4 times the original value.
4 0
3 years ago
A 0.38 kg drinking glass is filled with a hot liquid. The liquid transfers 7032 J of energy to the glass. If the
kaheart [24]

Answer:

841  J/kg.K

Explanation:

The computation of the specific hear of the glass is shown below:

As we know that

E= cmΔt

where

c denotes specific heat

m denotes 0.38 kg

Δt = temperature = 22k

E denotes energy = 7032 J

Now

7032 J = (0.38) (22) (c)

7032 J = 8.36 (c)

So C = 7032 J ÷ 8.36

= 841  J/kg.K

7 0
2 years ago
10. A person is about to kick a soccer ball. Consider the leg and foot to be a single rigid body and that it rotates about a fix
statuscvo [17]

Answer:

i don't know but i hope you get it right

Explanation

4 0
3 years ago
Other questions:
  • Two charged particles are located on the x axis. The first is a charge 1Q at x 5 2a. The second is an unknown charge located at
    9·1 answer
  • Express 50,000 m/s2 in scientific notation. 5.0 x 103m/s2 0.5 x 105m/s2 5.0 x 104m/s2
    8·2 answers
  • A 230-km-long high-voltage transmission line 2.0 cm in diameter carries a steady current of 1,100 A. If the conductor is copper
    12·2 answers
  • Name three ways in which an object can accelerate
    13·1 answer
  • Explain how it is possible for two different elements to have the same mass number
    10·2 answers
  • Calculate the energy extracted from 50g water vapour 100 ℃ to transform it into water at 80 Celsius.
    9·1 answer
  • ANSWER THIS FOR BRAINY CROWN B) ITS SO EASY!
    5·2 answers
  • Which statement describes how a machine can help make work easier? It can put out more force than the input force by decreasing
    14·2 answers
  • Please help i need it please​
    14·2 answers
  • What do these letters stand for<br> P=mv
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!