(a) 0.249 (24.9 %)
The maximum efficiency of a heat engine is given by
where
Tc is the low-temperature reservoir
Th is the high-temperature reservoir
For the engine in this problem,
Therefore the maximum efficiency is
(b-c) 0.221 (22.1 %)
The second steam engine operates using the exhaust of the first. So we have:
is the high-temperature reservoir
is the low-temperature reservoir
If we apply again the formula of the efficiency
The maximum efficiency of the second engine is
D: Sóng có thể truyền qua khoảng không của không gian,
với tốc độ ánh sáng.
Answer:
1.7 seconds
Explanation:
To clear the intersection, the total distance to be covered = 59.7 + 25 =84.7m
first we need to find the initial speed to just enter the intersection by using the third equation of motion
v^2 - u^2 = 2*a*s
45^2 - u^2 = 2 * -5.7 * 84.7
u^2 = 45^2 +965.58
u^2 = 2990.58
u = 54.7 m/s
Now for time we apply the first equation of motion
v-u =a * t
t = (v-u)/a = (45 - 54.7)/-5.7 = 1.7seconds
Answer: D. 0.5
Explanation:
The slope formula is y2-y1/x2-x1.
2-(-1)/4-(-2) = 2+1/4+2
2+1/4+2 = 3/6 = 1/2
1/2 = 0.5
The slope is 1/2, or 0.5.
