Answer:C
Explanation:
Power=280watts=280/1000 kilowatts
Power=0.28 kilowatts
Device use 0.28 kilowatts in 1 day
1day=24hours
Device use 0.28 kilowatts in 24hours
30days=30 x 24=720 hours
For 720 hours=(0.28x720) ➗ 24
For 720 hours=201.6 ➗ 24
For 720 hours=8.4
Power = (energy) / (time)
= (1370 joules) / (100 seconds)
= 13.7 joules/second
= 13.7 watts .
That's not an awful lot of power, especially for a strenuous activity like
rock-climbing. Shoot ! Even I could probably perform at that level.
Compare 13.7 watts to the light power coming out of a 20-watt night light.
13.7 watts = 0.018 horsepower. (rounded)
Answer:
The time taken for the commercial Jet liner to reach the end of its runway is 10.18 s.
Explanation:
Given;
average acceleration of the commercial Jet liner, a = 3g = 3 x 9.8 m/s² = 29.4 m/s²
distance traveled by the commercial Jet liner, s = 1542 m
The time taken for the commercial Jet liner to reach the end of its runway is calculated as follows;
s = ut + ¹/₂at²
where;
u is the initial velocity of the commercial Jet liner = 0
s = 0 + ¹/₂at²
s = ¹/₂at²
2s = at²
Therefore, the time taken for the commercial Jet liner to reach the end of its runway is 10.18 s.
This is because x is not an expanding part of the spring