Inverse Square Law of Light states that light intensity falls off rapidly with distance from its source. T<span>he intensity varies with the square of the flash-to-subject distance.
intensity at distance 1/intensity at distance 2=distance2^2/distance1^2
In our case, distance1=10m and distance2=20m, 20^2/10^2= 400/100=4, which means that t</span>he intensity of the wave<span> has increased by a factor of four.
Answer:D</span>
Power=work/time
power=50/20
50/20=2.5
Therefore A. 2.5 W
Answer:
Total charge flow through the cooker is 21600 C
Explanation:
As we know that the current flow through the cooker is given by Ohm's law
here it is given as




now the charge flow through it is given as

total time is t = 8 hours


We can use kinematics here if we assume a constant acceleration (not realistic, but they want a single value answer, so it's implied). We know final velocity, vf, is 1.0 m/s, and we cover a distance, d, of 0.47mm or 0.00047 m (1m = 1000mm for conversion). We also can assume that the flea's initial velocity, vi, is 0 at the beginning of its jump. Using the equation vf^2 = vi^2 + 2ad, we can solve for our acceleration, a. Like so: a = (vf^2 - vi^2)/2d = (1.0^2 - 0^2)/(2*0.00047) = 1,064 m/s^2, not bad for a flea!
<span>Poet Kuangchi Chang did not remain in China long enough to be "re-educated." Following the Communist takeover he fled to the United States. His poem "Garden of My Childhood" describes China before the revolution as a peaceful, idyllic garden with a violent horde rapidly approaching. A vine, the wind, and the sea are each personified, and each beckons for him to run. It is not until "eons later," when he is "worlds away," that his "running is all done," and he finds himself at his destination: another garden, just like the one he had left behind.</span>