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:
of the velocity of a full size plane in the air
Answer: B, they can land themselves now
Explanation:
Answer:
R = 4.77 ohms
Explanation:
Four resistors are given such that,
R₁ = 2 ohms
R₂ = 3 ohms
R₃ = 5 ohms
R₄ = 10 ohms
Here, R₁ and R₂ in series. The equivalent is given by :
R₁₂ = R₁ + R₂
= 2 + 5
R₁₂ = 7 ohms
Similarly, R₃ and R₄ are in series. so,
R₃₄ = R₃ + R₄
= 10+5
R₃₄ = 15 ohms
Now, R₁₂ and R₃₄ are in parallel. So,

So, the equivalent resistance s 4.77 ohms.
Answer: physical or mechanical weathering
Explanation:
Mechanical weathering which is also referred to as the physical weathering occurs when a rock is broken down into smaller pieces. In this case, there will be a physical change of the rock but its composition will not change.
Some examples include ice freezing and expansion of the cracks in the rock, Smstrong winds that carrycpieces of sand which then sandblast surfaces, moving water which causes abrasion etc.