Answer:
47 mW
Explanation:
The average value of the Poynting vector, S = 0.939 W/m² = Intensity of wave, I
S = I S
Also, I = P/A where P = Et, P = power of electromagnetic wave, E = energy of electromagnetic wave in time t and t = time = 1 min = 60 s and A = area = lb since the electromagnetic waves falls on area equal to that of a rectangle.
So, S = Et/A
E = SA/t
= Slb/t
= 0.939 W/m² × 1.5 m × 2.0 m/60 s
= 2.817 W/60 s
= 0.047 W
= 47 mW
So, 47 mW of electromagnetic energy falls on the area in 1.0 minute.
The correct answer among the choices given is the last option. Cora wrapping the copper wire with a thick plastic coating keeps a current from passing out a wire. The plastic wire here serves as an insulator. An insulator is a material that prevents electricity or current to flow out the circuit. In order to lessen the loss of energy.
HOPE THIS HELPS!
Answer:
Explanation:
The velocity of the swimmer just before touching the water is:
The average force exerted on the diver by the water is determined by the use of the Principle of Energy Conservation and the Work-Energy Theorem:
Answer:
<em>the minimum speed that the ball must have so that the cord does not become slack is</em> <em>2.02 m/s.</em>
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Explanation:
In order to avoid slack, the centripetal force of the ball must equal its weight at the top of the circle. Therefore,
F_c = F_g
m v² / r = m g
v² = g r
v = √[g r]
v = √[(9.8 m/s²)(0.417 m)]
<em>v = 2.02 m/s </em>
Therefore,<em> the minimum speed that the ball must have so that the cord does not become slack is</em> <em>2.02 m/s.</em>
Answer:
Since light travels faster than sound, the lightning arrives before the thunder. But thunder is the sound of lightning shooting through the sky in a thunderstorm.
Explanation:
