Answer:
28 metres
Explanation:
when the bag is about to hit the ground
potential energy = kinetic energy
where m = mass
g = acceleration due to gravity
v = speed
when you simplify the above equation and make v subject of the formular we have
where g = 9.8m/s
h = 40
Since the grains are not connected together, it's every grain for himself when they're dropped into the water.
The density of each grain is greater than the density of water, so each grain on its own sinks to the bottom.
The reason why a CUP or a BAG of rice has less density is because the grains don't all fit together perfectly, and 15% or 20% of the volume in the cup or bag is air, not rice grains.
<em>"Rice is the perfect snack, when you're hungry for 2000 of something."</em>
Mitch Hedberg
Answer:
Power= 0.5hp = 375W
T = 3hrs = 10800s
Power = Work done/ Time
Work = Power * Time = 375 * 10800 = 4050000J
The period T with which the current at the wall socket changes is 0.017 s.
It also ranges from 0.155 s to 0.0189 s since the cycles is not given in the question.
<u>Explanation</u>:
The current reaches 3.8 A once for every cycle. So there must have been 10 cycles (10 periods) in 0.17 s.
Using 'T' for period:
10 T = 0.17
T = 0.17 / 10
T = 0.017 s.
The question doesn't tell about the cycles and so we assume it as 10 cycles. If there are 9 cycles due to the current 3.8 A at the exact beginning and end of 0.17 s. This would make the period T as
0.17 / 9 = 0.0189 s approx.
Likewise, if the 3.8 A occurs at the end of the 1st cycle, 11 cycles would have passed during 0.17 s.
In that case the period = 0.17 / 11 = 0.155 s approx.
So T could be in the range from 0.155 s to 0.0189 s.