All categories

3 years ago

At a fabrication plant, a hot metal forging has a mass of 75 kg and a specific heat

Physics

1 answer:

Lesechka [4]3 years ago

3 0

Answer:

940°C

Explanation:

Heat lost by the forging = heat gained by the oil

-mCΔT = mCΔT

-(75 kg) (430 J/kg/°C) (47°C − T) = (710 kg) (2700 J/kg/°C) (47°C − 32°C)

-32250 (47°C − T) = 1917000 (15°C)

47°C − T = -892°C

T = 939°C

Rounded to two significant figures, the initial temperature is 940°C.

You might be interested in

A proton (mass=1.67x10^-27 kg, charge= 1.60x10^-19 C) moves from point A to point under the influence of an electrostatic force

Anettt [7]

Answer:

$VB - VA = - 33.4$

Explanation:

Generally the workdone in moving the proton is mathematically represented as

$W = KE_f - KE_i$

Where $KE_i \ and \ KE_f \ are\ the\ initial \ and \ final \ kinetic \ energy$

$KE_i = \frac{1}{2} m v_a^2$

Here $v_a$ is the velocity at A with value 50 m/s

$KE_i = \frac{1}{2} (1.67*10^{-27}) * 50^2$

$KE_i = 2.09 *10^{-24} \ J$

Also

$KE_f = \frac{1}{2} m v_b^2$

Here $v_a$ is the velocity at A with value $80 km/s = 80000 m/s$

=> $KE_f = \frac{1}{2} (1.67*10^{-27}) * 80000^2$

=> $KE_f = 5.34 *10^{-18} \ J$

$W = 5.34 *10^{-18} - 2.09 *10^{-24}$

$W = 5.34 *10^{-18} m/s$

Now this workdone is also mathematically represented as

$W = q * V$

$q * V = 5.34 *10^{-18}$

Here $q = 1.60*10^{-19} C$

$V = \frac{5.34 *10^{-18} }{1.60*10^{-19}}$

$V = 33.4 \ V$

Generally proton movement is in the direction of the electric field it means that $VA>VB$

$VB - VA = - 33.4$

6 0

3 years ago

Temperature difference in the body. The surface temperature of the body is normally about 7.00 ∘C lower than the internal temper

Nikolay [14]

Answer:

Temperature difference in kelvin =7K

Temperature difference in Fahrenheit degree = 12.6°F

Explanation:

Temperature difference = 7°C

273 is added to the Celsius value to convert to kelvin temperature.However if 273 is added to both the initial and final values of the Celsius temperature values, then the difference still stays the same. Hence the difference in kelvin is 7K.

To convert the temperature difference to Fahrenheit we simply multiply 1.8

=7*1.8 = 12.6°F

8 0

3 years ago

An athlete stretches a spring an extra 28.6 cm beyond its initial length. how much energy has he transferred to the spring, if t

g100num [7]

PE = 0.5 × k × x²

PE potential Energy
k spring constant
x stretch/compression of the spring

6 0

3 years ago

Yoga not only builds flexibility, but strength and balance.<br><br> True or False

azamat

Answer:

True

Explanation:

I just know.

3 0

2 years ago

Which of the following body systems work together to get sells the oxygen they need to carry at the cellular respiration

djyliett [7]

The cells in your body help get oxygen to cellular respiration.

8 0

3 years ago