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3 years ago

Please I need help with this question (see image).Show workings where necessary.

Physics

1 answer:

Andrews [41]3 years ago

4 0

Answer:

Solution:

i) Heat supplied by heater = Heat gained by water = m * c*theta = 0.12Kg * 4200 * 10 = 5040Joules in 2 minutes.

ii) Power = Energy/time = 5040J/(2 * 60seconds) = 5040J/120seconds = 42Watts.

(iii) Heat supplied to the 70g of water = m * c * theta = 0.07Kg * 4200 * 9K = 2646J

(iv) Heat supplied by heater = Heat gained by 70g of water + Heat supplied to the metal vessel.

But,from our calculations above,

Heat supplied by heater = 5040J ......and

Heat supplied to the 70g of water = 2646J

.: substituting the values,we have that :

5040J = 2646J + Heat supplied to the metal vessel.

5040J - 2646J = Heat supplied to the metal vessel.

.: Heat supplied to the metal vessel = 2394J.

(v) Heat gained by metal vessel = Heat capacity of the vessel * theta.

2394J = Heat capacity of the vessel * 9K

.: Heat capacity of the vessel = 2394/9 = 266(Joule per Kelvin)

(vi) Using the formula:

Heat Capacity = mass * specific heat capacity

.: Specific heat capacity = Heat Capacity/mass = 266/0.55 = 484(Joules per Kilogram per Kelvin)

Explanation:

<h3>________❤️ hope it helps you ❤️__________</h3>

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