Answer:15,883.63 KJ
Explanation:
Given
Power=400 W
Freezing compartment temperature is 273 K
Outside air Temperature=306 K
Time =80 minutes
Energy Required to deliver 400 w power in 80 minutes
E=1920 KJ
and we know COP of refrigerator is given by
Therefore 15,883.63 KJ is removed in 80 minutes
The correct option is D.
Sound proofing is usually achieved by using materials that absorbed or reduce sounds. Different materials are used in sounding proofing and these differ in their abilities to absorb or reduce sounds. The coefficient of absorption of a material refers to that material ability to absorb sound. The higher the percentage of a material absorption coefficient, the better the material's ability to absorb sound. Thus, in the question given above, the material with 62% absorption coefficient have the greatest ability of the three materials to absorb sound effectively. <span />
Average velocity = (displacement) / (total time)
Displacement = distance and direction between
the starting point and the end point
The car travels 90 meters north, then 40 meters south.
So it ends up 50 meters north of where it began.
Displacement = 50 meters north
Total time = (15 + 5) = 20 seconds
Average velocity = (50 meters north) / (20 seconds)
= 2.5 m/s north
