So it would be 12 minutes and $5 per 12 minutes.
Answer:
The total weight of the metal bar in pounds is 25 pounds
Step-by-step explanation:
Now, we have a metal bar which has a content of 60% zinc corresponding to 15 pounds.
Mathematically, let’s say the total weight of the metal composite is x pounds. It is 60% of this that is 15 pounds which is the content of the zinc
Mathematically;
60/100 * x = 15
60x = 15 * 100
60x = 1500
x = 1500/60
x = 25 pounds
<span>1. How much heat is absorbed by a 50g iron skillet when its temperature rises from 10oC to 124oC? Joules
Formula: Heat = mass * specific heat * ΔT
Data:
mass = 50 g = 0.050 kg
specific heat of iron = 450 J/ kg °C
ΔT = 124°C - 10°C ¿ 114 °C
=> heat = 0.050kg * 450 J / kg°C * 114°C ≈ 2.6 J
2. If a refrigerator is a heat pump that follows the first law of
thermodynamics, how much heat was removed from food inside of the
refrigerator if it released 492J of energy to the room? Joules
The firs law of thermodynamics is conservation of energy => energy removed from inside of the refrigerator = energy released to the room
=> Answer = 492 J
3. How much heat is needed to raise the temperature of 45g of water by 63oC? Joules
Formula: heat = mass * specific heat * ΔT
specific heat of water = 4186 J / Kg °C
heat = 0.045 kg * 4186 J/kg °C * 63°C = 11,867.31 J
</span>
(5b)(-3a)
= (5*(-3))(b*a) (combine like terms)
= -15ab
The final answer is -15ab~