Answer:
(a) Heat transfer to the environment is: 1 MJ and (b) The efficiency of the engine is: 41.5%
Explanation:
Using the formula that relate heat and work from the thermodynamic theory as: solving to Q_out we get: this is the heat out of the cycle or engine, so it will be heat transfer to the environment. The thermal efficiency of a Carnot cycle gives us: where T_Low is the lowest cycle temperature and T_High the highest, we need to remember that a Carnot cycle depends only on the absolute temperatures, if you remember the convertion of K=°C+273.15 so T_Low=150+273.15=423.15 K and T_High=450+273.15=723.15K and replacing the values in the equation we get:
Answer:
is the drop in the water temperature.
Explanation:
Given:
- mass of ice,
- mass of water,
Assuming the initial temperature of the ice to be 0° C.
<u>Apply the conservation of energy:</u>
- Heat absorbed by the ice for melting is equal to the heat lost from water to melt ice.
<u>Now from the heat equation:</u>
......................(1)
where:
latent heat of fusion of ice
specific heat of water
change in temperature
Putting values in eq. (1):
is the drop in the water temperature.
Answer:
7.72 Liters
Explanation:
normal body temperature = T_body =37° C
temperature of ice water = T_ice =0°c
specfic heat of water = c_{water} =4186J/kg.°C
if the person drink 1 liter of cold water mass of water is = m = 1.0kg
heat lost by body is Qwater =mc_{water} ΔT
= mc{water} ( T_ice - T_body)
= 1.0×4186× (0 -37)
= -154.882 ×10^3 J
here negative sign indicates the energy lost by body in metabolic process energy expended due to brisk - hour long walk is Q_{walk} = 286 kilocalories
= 286×4186J
so number of liters of ice water have to drink is
n×Q_{water} =Q_{walk} n= Q_{walk}/ Q_{water}
= 286×4186J/154.882×10^3 J
= 7.72 Liters
Answer:
nods 40th anniversary rid off e 49en9 snns
The velcocity equals acceleration times time
which is 50 ms per sec