Answer:
the correct representation of the trough is b
If 56.5kJ are needed to raise the temp by 90°C and if the heater is 60% efficient that means that:
60% X y = 56.5kJ
where y is the electrical energy in kJ that the heater will use.
y = 94.2kJ
Answer:
84 kj/min = 1.4 kj/sec
Power Out / Power In = Heat Out / Heat In - Coefficient of Performance
1.4 kj/sec / 1.2 kj/sec = 1.17 = COP
Answer:
false
Explanation:
Understand Newton’s first law of motion. Experience suggests that an object at rest will remain at rest if left alone, and that an object in motion tends to slow down and stop unless some effort is made to keep it moving. An object will go on forever if there were no forces to act upon it. In space, a rocket will go forever at the speed it projects.
Answer:
1. 571.43m/s
2. 142.9m and 342.9m
Explanation:
1.Take the difference in time.
1.2-0.7=0.7 seconds
Take the distance between them and divide with differnce in time.
400÷0.7=571.43 seconds.
2.Take the time of the two men and divide by two.
0.5÷2= 0.25 secs
1.2÷2= 0.6 secs
multiply each with the velocity.
0.25×571.43=142.9m
0.6×571.43=342.9m
