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
dangina [55]
3 years ago
6

An engine absorbs 1749 J from a hot reservoir and expels 539 J to a cold reservoir in each cycle. a. What is the engine’s effici

ency? b. How much work is done in each cycle? c. What is the power output of the engine if each cycle lasts for 0.305 s?
Physics
1 answer:
Masja [62]3 years ago
8 0

Answer:

a)η = 69.18 %

b)W= 1210 J

c)P=3967.21 W

Explanation:

Given that

Q₁ = 1749 J

Q₂ = 539  J

From first law of thermodynamics

Q₁   = Q₂ +W

W=Work out put

Q₂=Heat rejected to the cold reservoir

Q₁ =heat absorb by hot  reservoir

W= Q₁- Q₂

W= 1210 J

The efficiency given as

\eta=\dfrac{W}{Q_1}

\eta=\dfrac{1210}{1749}

\eta=0.6918

η = 69.18 %

We know that rate of work done is known as power

P=\dfrac{W}{t}

P=\dfrac{1210}{0.305}\ W

P=3967.21 W

You might be interested in
Desde que altura debes de lanzar una canica de 50g para que adquiera una energia de 100j
AnnZ [28]

Answer:

204 m

Explanation:

When the marble is dropped from a certain height, its gravitational potential energy converts into kinetic energy. So the kinetic energy gained is equal to the variation of gravitational potential energy:

\Delta U=mg\Delta h

where

m is the mass of the marble

g = 9.8 m/s^2 is the acceleration of gravity

\Delta h is the change in height

In this problem, we have

m = 50 g = 0.05 kg

\Delta U = 100 J

Solving the formula for \Delta h, we find the necessary height from which the marble should be dropped:

\Delta h = \frac{\Delta U}{mg}=\frac{100}{(0.05)(9.8)}=204 m

7 0
3 years ago
Carlos was camping and getting cold as the sun went down. He wanted to light a fire for warmth and light. However, he discovered
storchak [24]
1. The chemical reaction produced by Carlo's fire is exergonic because energy is "going out". As the reaction proceeds, entropy increases as the energy stored in the dry wood and leaves are used up as fuel to create the fire which produces low quality light and warmth.  

2. This reaction is a classic example of an exothermic reaction. Exothermic reactions are characterized with the presence of heat and light in the products. Combustion reactions are always exothermic in nature.

3. Catalyst are substances that are used to speed up reactions by lowering the activation requirement. Catalysts aren't consumed in the reaction and can still be chemically retrieved afterwards. In this situation, the leaves cannot be retrieved after the reaction ends. The leaves speed up the heating of the wood but it does not behave as a catalyst. 
6 0
3 years ago
In the ground state of hydrogen, according to the Bohr model, an electron orbits 5.3 x 10-11 m from the nucleus. It undergoes a
Readme [11.4K]

Answer:

Explanation:

Given

radius of electron(r)=5.3\times 10^{-11} m

centripetal acceleration (a_c)=9\times 10^22 m/s^2

we know

a_c=\frac{v^2}{r}

v=\sqrt{r\times a_c}

v=\sqrt{5.3\times 10^{-11}\times 9\times 10^{22}}

v=\sqrt{47.7\times 10^11}

v=21.84\times 10^5 m/s

(b)For n=10

r=100\times 5.3\times 10^{-11} m\approx 5.3\times 10^{-9} m

a_c=10^4\times 9\times 10^{22} m/s^2

a_c=9\times 10^{26} m/s^2

v=\sqrt{r\times a_c}

v=\sqrt{9\times 10^{26}\times 5.3\times 10^{-9}}

v=21.84\times 10^8 m/s

8 0
3 years ago
If we add 50 Joules of thermal energy to a heat engine, and that heat engine does 30 Joules of work, how much thermal energy is
Natalka [10]

Answer:

The correct answer should be

A. 20 Joules

Explanation:

I'm taking the K12 Unit Test: Energy - Part 1 right now

7 0
2 years ago
Help will mark brain list
Hatshy [7]
A jagged line represents a resistor .
3 0
2 years ago
Other questions:
  • Only two forces act on an object (mass = 3.80 kg), as in the drawing. (F = 51.0 N.) Find the magnitude and direction (relative t
    5·1 answer
  • Helppppppp pleassseeee!!!!!!
    9·1 answer
  • If a single strand of DNA were stretched out, how far would it reach?
    12·2 answers
  • A tennis ball rolls off the edge of a table. the table is 0.55m tall and the tennis ball lands 0.12m away from the table.
    14·1 answer
  • If an object of mass m1 = 0.55 ???????? is sliding without friction in the +x-direction on a level surface at a speed of ????1 =
    6·1 answer
  • Can you hear this Picture???<br>If you know it, you get it
    6·1 answer
  • The mass of a baseball is 100 grams and the volume is 25 cm cubed. What is the density?
    6·2 answers
  • First aid for a strain or a sprain
    5·1 answer
  • Question 2 of 5
    7·1 answer
  • falling parachutist you bail out of the helicopter of example 3 and pull the ripcord of your parachute. now in eq. (3), so your
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!