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
Goryan [66]
3 years ago
7

A 200 g piece of iron is heated to 100°C. It is then dropped into water to bring its temperature down to 22°C. What is the amoun

t of heat transferred to water? (ciron = 0.444 J/g°C) A) 1.9 kJ B) 6.9 kJ C) 8.9 kJ Eliminate D) 10.9 kJ
Physics
2 answers:
Amiraneli [1.4K]3 years ago
8 0
The piece of iron is brought from a temperature of 100C to a temperature of 22C. In this process, the heat released by this piece of iron is
Q=m C_s \Delta T
where m=200 g is the mass of the piece of iron, C_s = 0.444 J/(g C) is the iron's specific heat, and the temperature variation is \Delta T = 22^{\circ}-100^{\circ}=-78^{\circ}C. Using these values, the amount of heat released by the iron is
Q=(200 g)(0.441 J/(gC))(-78C)=-6926J=-6.9 kJ
With negative sign because it is amount of heat released. This heat is then trasferred to the water, so the amount of heat absorbed by the water is Q=6.9 kJ.
ASHA 777 [7]3 years ago
5 0

The answer is B) 6.9 kJ.

You might be interested in
Si dos aparatos eléctricos que tienen diferente potencia funcionan durante el mismo tiempo, ¿ cual transformara mayor cantidad d
Brilliant_brown [7]

Answer: I dont undertand sorry

Explanatio

5 0
3 years ago
Two electrons are at rest and separated by a distance of 4.32 × 10-10 m. When they are released they accelerate away from each o
sasho [114]

Answer:

Speed of electron when their separation increased by a factor of 4.10 is 9.41 x 10⁵ m/s .

Explanation:

The electric potential energy is given by the relation :

U = \frac{kq_{1}q_{2}  }{r}

Here q₁ and q₂ are the two charge particles and r is the distance between them and k is electric constant.

In this case, there are two electrons which are separated by the distance 4.32 x 10⁻¹⁰ m.

Let e be the electron charge and r₁ be the distance between them. Then, the initial electric potential energy is :

U_{1}  = \frac{ke^{2}   }{r_{1} }

Now, the distance between the electrons increases by the factor of 4.10. Let r₂ be the new distance between them i.e. r₂ = 4.10 r₁.

Thus, the new electric potential energy is :

U_{2}  = \frac{ke^{2}   }{r_{2} }=\frac{ke^{2}   }{4.10r_{1} }

Applying law of conservation of energy :

ΔU  = ΔK

Here ΔU is change in electric potential energy and ΔK is change in kinetic energy.

( U₁  - U₂ ) = ( K₂ - K₁ )

Here K₂ and K₁ are initial and final kinetic energy of electron.

Since, the electron initially is at rest, so its initial kinetic energy is zero. Thus, the above equation becomes:

K₂ = U₁ - U₂

\frac{1}{2}mv^{2}=\frac{ke^{2}   }{r_{1} }- \frac{ke^{2}   }{4.10r_{1} }

Here m and v are the mass and final speed of electron respectively.

v^{2}=\frac{2}{m} \frac{ke^{2}   }{r_{1} }(1- \frac{1  }{4.10 })

Substitute 9.1 x 10⁻³¹ kg for m, 9 x 10⁹ N m² C⁻² for k, 1.6 x 10⁻¹⁹ C for e and 4.32 x 10⁻¹⁰ m for r₁ in the above equation.

v^{2}=\frac{2}{9.1\times10^{-31} } \frac{9\times10^{9}\times(1.6\times10^{-19})^{2}   }{4.32\times10^{-10} }(1- \frac{1  }{4.10 })

v^{2}=8.86\times10^{11}

v = 9.41 x 10⁵ m/s

5 0
3 years ago
Which planets are closets to the sun?
damaskus [11]

The plant that is closest to the sun is murcury. Then it is venus, then earth, and then mars. Then it is jupiter, then saturn, then uranus, then neptune.

5 0
3 years ago
Read 2 more answers
What is the function of mitochondria? BRAINLIEST WILL BE GIVEN PLS HELP
Citrus2011 [14]

Answer:

The Mitochondria generates most of the chemical energy needed to power the cell's biochemical reactions.

Explanation:

I studied the body organisms 2 years ago.

7 0
2 years ago
Read 2 more answers
Name one metal and one non-metal from the periodic table? <br><br> Y’all I need help<br> Thank you!
Stella [2.4K]

Answer:

Zinc and Neon!

Explanation:

zinc is an element that is a transition metal and neon is a noble gas

8 0
3 years ago
Other questions:
  • A hot air balloon has a mass of 300 k gincluding the basket. The hot air inside the balloon weighs 17,000 N. Determine the maxim
    13·1 answer
  • A soil sample is 25 percent sand, 55 percent clay, and 20 percent silt. Use the following soil texture triangle to determine the
    14·1 answer
  • Choose the scientific notation that best represents the standard notation given. 6,840,000,000 m 68.4 x 108 m 6.84 x 108 m 6.84
    12·2 answers
  • An object of mass 10 kg is at rest when a net force of 20 N acts on it in a direction east. The acceleration produced on the obj
    5·1 answer
  • Positional and non positional different between​
    8·1 answer
  • Plate] term 3 quiz 1 physics grade 9
    8·1 answer
  • how does the tilt of earth affect the hours of daylight north of the tropical of cancer at the time of year shown?​
    8·1 answer
  • The problem of perception is best characterized as
    15·1 answer
  • How can a single crash of a car into a wall involve three separate collections?
    8·1 answer
  • aqueos barium chloride reacts with aqueous sodium sulfate to produce solid barium sulfate and aqueous sodium chloride
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!