A nail driven into a board increases in temperature. If we assume that 60 % of the kinetic energy delivered by a 1.80-kg hammer with a speed of 7.80 m/s is transformed into heat that flows into the nail and does not flow out, what is the temperature increase of an 8.00-g aluminum nail after it is struck ten times?

Respuesta :

Answer:

[tex]\Delta T=45.63^{\circ}C[/tex]

Explanation:

Given:

  • mass of hammer, [tex]m=1.8\ kg[/tex]
  • speed of the hammer, [tex]v=7.8\ m.s^{-1}[/tex]
  • part of kinetic energy of hammer getting transformed into heat, [tex]F=60\%[/tex]
  • mass of nail, [tex]m'=8\ g=0.008\ kg[/tex]
  • we've specific heat of aluminium, [tex]c=900\ J.kg^{-1}.^{\circ}C^{-1}[/tex]

Total kinetic energy given to the nail:

[tex]KE=10\times \frac{1}{2} \times m.v^2[/tex] (Since the aluminium nail is struck 10 times)

The heat that flows to the nail is 0.6 times of the total kinetic energy:

[tex]Q=0.6\times 10\times 0.5\times1.8\times 7.8^2[/tex]

[tex]Q=328.536\ J[/tex]

From the equation of heat:

[tex]Q=m'c.\Delta T[/tex]

[tex]328.536=0.008\times 900\times \Delta T[/tex]

[tex]\Delta T=45.63^{\circ}C[/tex] is the increase in the temperature of the nail.

The increase in the temperature will be "45.63°C".

According to the question,

Mass,

  • [tex]m = 1.8 \ kg[/tex]

Speed,

  • [tex]v = 7.8 \ m.s^{-1}[/tex]

K.E getting transformed,

  • [tex]F = 60[/tex]%

Mass of nail,

  • [tex]m' = 8 \ g[/tex]

or,

             [tex]= 0.008 \ kg[/tex]

Specific heat,

  • [tex]c = 900 \ J.kg^{-1}.^{\circ} C^{-1}[/tex]

Now,

The total K.E given to the nail will be:

= [tex]10\times \frac{1}{2} mv^\\2[/tex]

The heat flows will be:

[tex]Q = 0.6\times 10\times 0.5\times 1.8\times 7.8^2[/tex]

   [tex]= 328.536 \ J[/tex]

By using the equation of heat, we get

→         [tex]Q = m'c.\Delta T[/tex]

→ [tex]328.536=0.008\times 900\times \Delta T[/tex]

→       [tex]\Delta T = 45.63^{\circ} C[/tex]

Thus the above response is correct.  

Learn more:

https://brainly.com/question/13188408

RELAXING NOICE
Relax