I beleive she isnt doing any work due to holding the box motionless, you must be exerting a force in the direction of the box motion. If she is just standing there holding the box their isn't no work becuase no distance has been covered. work = force = distance.
The minimum number of tickets that could admit all of them is six (6).
This thing is impossible to explain in words, so I shall attempt it with a diagram:
Here are the six ladies:
( A ) ( B )
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( C ) ( D )
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( E ) ( F )
-- 'E' and 'F' are the daughters of 'C' and 'D' .
-- 'C' and 'D' are the daughters of 'A' and 'B' .
So look what we have now:
-- 'A' and 'B' are the mothers of 'C' and 'D' .
There's 2 of the mothers.
-- 'C' and 'D' are the mothers of 'E' and 'F' .
There's the OTHER 2 mothers.
-- 'A' and 'B' are the grandmothers of 'E' and 'F' .
There's the 2 grandmothers.
-- 'E' and 'F' are the daughters of 'C' and 'D' .
There's 2 of the daughters.
-- 'C' and 'D' are the daughters of 'A' and 'B' .
There's the OTHER 2 daughters.
You want to know what ? !
The group is even bigger than THAT.
There are also 2 GRAND-daughters in the family ... 'E' and 'F' .
So now you have a list of 12 people ! ... 4 mothers, 2 grandmothers,
4 daughters, and 2 grand-daughters ... and they all get in to the
Christmas Market with only six tickets. Legally !
Such a deal !
Don't forget : Christmas this year is also the first day of Chanukah !
All for the same price !
Answer:
The angle of incidence when the reflected ray is perpendicular to the incident ray = 45°
Explanation:
According to Snell's Law,
n₁ sin θ₁ = n₂ sin θ₂
When the angle between the incident ray and reflected ray is 90°, the angle of incidence is θ₁ and the angle of reflection, θ₂ = 90° - θ₁ and the index of refraction in the Snell's Law for both media would be the same, n₁ = n₂ = n
n sin θ₁ = n sin (90° - θ₁)
Note that from trigonometric relations,
Sin (90° - θ₁) = cos θ₁
n sin θ₁ = n cos θ₁
(sin θ₁)/(cos θ₁) = 1
tan θ₁ = 1
θ₁ = arctan 1 = 45°
Hope this Helps!!!
