Physics, 31.07.2019 19:10 edmundg2238

20. a car battery with a 12-v emf and an internal resistance of 0.050 ω is being charged with a current of 60 a. note that in this process, the battery is being charged. (a) what is the potential difference across its terminals? (b) at what rate is thermal energy being dissipated in the battery? (c) at what rate is electric energy being converted into chemical energy

Answers: 1

Show answers

Answers

Answer from: godisgoodallthoubxi7

Part a)

V = 15 Volts

Part b)

P = 180 Watt

Part c)

Rate = 720 Watt

Explanation:

Part a)

When battery is in charging then the potential difference of the terminals of cell is given by

$\Delta V = EMF + iR$

here we know that

EMF = 12 volts

i = 60 A

r = 0.050 ohm

now we have

$\Delta V = 12 + (0.050)(60) = 15 Volts$

Part b)

Rate of thermal energy dissipated is the energy which is dissipating across the resistor

so here we have

P = i^2 R

P = (60^2)(0.05)

P = 180 Watt

Part c)

Rate at which Energy stored inside the cell is the rate of electrical energy that is converted into the chemical energy

$Rate = EMF \times i$

Rate = (12)(60)

Rate = 720 Watt

Answer from: Quest

none, its a machine

Answer from: Quest

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

$f\alpha \frac{dp}{dt}$

⇒ $f= k \frac{dp}{dt}$

here k is the proportionality constant whose value is 1.

$f=\frac{dp}{dt}$

$f= \frac{d[mv]}{dt}$

$f= m\frac{dv}{dt} +v\frac{dm}{dt}$

$f=ma+v\frac{dm}{dt}$ [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.

Another question on Physics

Physics, 21.06.2019 23:00

Acoal-fired plant generates 600 mw of electric power. the plant uses 4.8 x 10^6 kg of coal each day, and the heat of combustion of coal is 3.3x 10^7 j/kg. the steam that drives the turbines is at a temperature of 300° c, and the exhaust water is at 37° c. (a) what is the overall efficiency of the plant for generating electric power? (b) how much thermal energy is exhausted each day? (c) what is the change in entropy of the universe for this heat engine? (d) using the same heat reservoirs, what is the maximum possible (carnot) efficiency for a heat engine?

Answers: 1

Answer

Physics, 22.06.2019 02:00

Which safety measures should you follow during a thunderstorm? check all that apply. (a) avoid touching anything that conducts electricity. (b) avoid touching a person who has been struck by lightning. (c) go outside. (d) keep your computer turned off. (e) stay out of water. (f) stay inside.

Answers: 2

Answer

Physics, 22.06.2019 04:00

When an object is heated it contracts. a. true b. false

Answers: 2

Answer

Physics, 22.06.2019 06:20

Clothing made of several thin layers of fabric with trapped air in between, often called ski clothing, is commonly used in cold climates because it is light, fashionable, and a very effective thermal insulator. so it is no surprise that such clothing has largely replaced thickand heavy old-fashioned coats. (a) consider a jacket made of five layers of 0.1-mm-thick synthetic fabric (k = 0.13 w/m·°c) with 1.5-mm-thick air space (k = 0.026 w/m·°c) between the layers. assuming the inner surface temperature of the jacket to be 28°c and the surface area to be 1.25 m2, determine the rate of heat loss through the jacket when the temperature of the outdoors is 0°c and the heat transfer coefficient at the outer surface is 25 w/m2·°c. (b) what would your response be if the jacket is made of a single layer of 0.5-mm-thick synthetic fabric? what should be the thickness of a wool fabric (k = 0.035 w/m·°c) if the person is to achieve the same level of thermal comfort wearing a thick wool coat instead of a five-layer ski jacket?

Answers: 1

Answer

You know the right answer?

20. a car battery with a 12-v emf and an internal resistance of 0.050 ω is being charged with a curr...

Questions