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
Tatiana [17]
3 years ago
11

Maria and Miquel were enjoying the fireworks when they got into a chemistry argument. Maria insisted that the fireworks were the

result of a chemical reaction. Miguel disagreed. What would you tell them to solve this argument? A) It is a change of state, solid to gas, due to the addition of energy. B) It was a physical reaction since the fuse was lit and heat was produced. C) The color changes and the release of energy indicate a chemical reaction. D) It is an endothermic reaction because energy was added; therefore it is a chemical reaction, Eliminate
Physics
2 answers:
mart [117]3 years ago
8 0

the answer is C, The color changes and the release of energy indicate a chemical reaction. hope that helps, :)

Tcecarenko [31]3 years ago
5 0
In this case, there is a chemical reaction where there is the burning of fuels that can vary between some within the periodic table, but when the fuel is burned a reaction occurs that gives the coloration the explosions of the fires.
You might be interested in
Assume your mass is 60 kg. The acceleration due to gravity is 9.8 m/s 2 . How much work against gravity do you do when you climb
Andre45 [30]

Answer:

W=1705.2 J

Explanation:

Given that

mass ,m= 60 kg

Acceleration due to gravity ,g= 9.8 m/s²

Height ,h= 2.9 m

As we know that work done by a force given as

W = F . d

F=force

d=Displacement

W=work done by force

Now by putting the values

F= m g (Acting downward  )

d= h  (Upward)

W= m g h    ( work done against the force)

W= 60 x 9.8 x 2.9 J

W=1705.2 J

Therefore the answer will be 1705.2 J.

8 0
3 years ago
A light horizontal spring has a spring constant of 138 N/m. A 3.35 kg block is pressed against one end of the spring, compressin
BARSIC [14]

Answer:

U_k = 0.113

Explanation:

using the law of the conservation of energy:

E_i -E_f=W_f

\frac{1}{2}Kx^2=NU_kd

where K is the spring constant, x is the spring compression, N is the normal force of the block, U_k is the coefficiet of kinetic friction and d is the distance.

Also, by laws of newton, N is calculated by:

N = mg

N = 3.35 kg * 9.81 m/s

N = 32.8635

So, Replacing values on the first equation, we get:

\frac{1}{2}(138)(0.123)^2= (32.8635)U_k(0.281m)

solving for U_k:

U_k = 0.113

8 0
3 years ago
A year 11 pupil with a mass of 55kg swinging back on their chair and falling off it at a speed of 0.6m/s. What is his kinetic en
posledela

Answer:

Uk = 9.9 J

Explanation:

To calculate the kinetic energie (Uk), you can make use of this formula:

Uk = 0.5 * m * v²

given m = 55 kg and v = 0.6 m/s

Substituting in the formula gives:

Uk = 0.5 * 55 * (0.6)²

Uk = 0.5 * 55 * 0.36

Uk = 9.9 J

Extra:

Now let's examine the formula in relation to the SI units. <em>If you understand the following, it will give you great insight in how smart Phisics is inter twained by looking at formulas and their standard units. It will save you time in future to convert formulas, if you use the right standard units.</em>

The formula for kinetic energie is:

Uk = 0.5 * m * v²

Standard SI unit for mass m is kg.

Standard SI unit for speed v is m/s.

So v * v = v² and therefore v² must have the standard SI unit of m²/s².

From the formula, you see that the unit of Uk must be kg*m²/s² and since Uk is normally given in J, these both forms must be the same !

The main unit for Uk is the Joule. <em>Now</em><em> </em><em>please</em><em> </em><em>see</em><em> </em><em>the</em><em> </em><em>picture</em><em>,</em><em> </em><em>which</em><em> </em><em>shows</em><em> </em><em>the </em><em>relation</em><em> </em><em>between </em><em>the </em><em>J </em><em>and </em><em>other</em><em> SI units</em><em>.</em><em> </em><em>Please</em><em> </em><em>understand</em><em> </em><em>that</em><em> </em><em>you</em><em> </em><em>can</em><em> </em><em>construct</em><em> </em><em>your</em><em> </em><em>'own'</em><em> </em><em>formulas</em><em> </em><em>based</em><em> </em><em>these</em><em> </em><em>units</em><em>.</em><em> </em><em>Now</em><em> </em><em>here</em><em> </em><em>is</em><em> </em><em>the</em><em> </em><em>time</em><em> </em><em>saver</em><em>:</em>

Because almost always the right units are <em>given</em> in a question, or because sometimes you can look up a constant in a table with an exotic and seemingly complicated unit, but that says a lot about the formula which must have been some how involved!

<em>By this, I hope you now understand the implication of using the right standard SI units and how that can help you figure out what formula is needed.</em>

3 0
3 years ago
What kind of system does not allow matter or energy to enter or exit?
Vilka [71]

a closed system does not allow matter or energy to pass through

6 0
3 years ago
Any transparent material that allows light of only certain color to pass through is called a filter . true or false
Dahasolnce [82]

it is TRUE hope this helps

7 0
3 years ago
Other questions:
  • My parrot has a mass of 1.33kg, what is it's weight here on earth​
    6·1 answer
  • Why is Pluto not considered a planet?
    7·2 answers
  • A loop circuit has a resistance of R1 and a current of 2.2 A. The current is reduced to 1.6 A when an additional 2.8 Ω resistor
    9·1 answer
  • Peer pressure is the influence that _________ may have on you
    5·2 answers
  • a box is pushed 40 m by a mover. the amount of work done was 2,240j. how much force was exerted on the box a box is pushed 40 m
    11·2 answers
  • What are the units for gravitational field strength ?
    15·2 answers
  • What material was the hindenburg made of?
    5·1 answer
  • A parallel-plate capacitor is made from two aluminum-foil sheets, each 3.0 cm wide and 5.00 m long. Between the sheets is a mica
    12·1 answer
  • 11. A roller coaster car is moving slowly up a long ramp to the very top of the roller coaster. It goes over the top and starts
    6·1 answer
  • 10. A kicked soccer ball has an initial velocity of 30 m/s at an angle of 42° above the horizontal, level
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!