Answer:
The answer to this is D two of the above
Answer:
A
Explanation:
Momentum is mass times velocity.
A. 275 kg × 0.55 m/s = 151.25 kgm/s
B. 2.7 kg × 7.5 m/s = 20.25 kgm/s
C. 91 kg × 1.4 m/s = 127.4 kgm/s
D. 1.8 kg × 6.7 m/s = 12.06 kgm/s
So A has the greatest momentum.
The thermal efficiency of a combustion system is simply
the ratio of heat out and heat in, that is:
efficiency = heat out / heat in
efficiency = 1030 J / 1540 J
efficiency = 0.669
<span>So the efficiency is 0.669</span>