Answer: Shorter
Explanation: Shadow is formed when an light source is obstructed by an opaque object. The closer the source, shorter is the length of the shadow. In fact, when the source is exactly overhead, no shadow of the object is formed.
June 21 marks the Summer solstice which means the Sun passes directly overhead Tropic of cancer (23.5° N) at noon. March 21 marks the equinox which means sun passes directly overhead equator (0°).
Shadow length of an object at 42° Northern latitude will be shorter on June 21 because the Sun will be closer to this latitude as compared to March 21.
<span>E=hc/wav. len
E = (6.62 x 10^-34 x 3 x 10^8)/0.0275 x 10^-9
E = 7.22182 x 10^-15 J
To convert to eV divide by 1.6 x 10^-19
E = 7.22182 x 10^-15/1.6 x 10^-19 eV
E =45.36 x 10^3 eV
Th energy, E, of a single x-ray photon in eV is = 45.36keV.
Number of photons, n = total energy/ energy of photon
n = 3.85 x 10^-6/7.22182 x 10^-15
n = 5.33 x 10^8 photons </span>
(a) The force exerted by the electric field on the plastic sphere is equal to

where

is the charge of the sphere and E is the strength of the electric field. This force should balance the weight of the sphere:

where m is the mass of the sphere and g is the gravitational acceleration.
Since the two forces must be equal, we have:

and so we find the intensity of the electric field

(b) Now let's find the direction of the field. The electric force must balance the weight of the sphere, which is directed downward, so the electric force should be directed upward. Since the charge is negative, the force is opposite to the electric field direction, and so the direction of the electric field is downward.
1) sound velocity reported by you : 292.39 m /s
2) time to travel 1620m at that velocity: t = d / v = 1620 m / 292.39 m/s = 5.54 s, since the moment the sound wave started.
3) You might wanted to tell the time since you watched the lightning.
Then you can calculate the time since the lighting was generated,1620 m away from you, until you saw it, using the speed of light:
speed of light = 3*10^8 m/s => t = 1620 m / (3*10^8m/s) =0.0000054 s
Then, this time is completely neglectible, and yet the answer is 5.54 s, as calculated in the step 2.