Answer:
option D
Explanation:
given,

increase the intensity by factor of 9
I₁ = I₀
I₂ = 9 I₀
now,




A₂ = 3 A₁
hence, amplitude increase with the factor of 3
so, the correct answer is option D
Answer:
W = -1844.513 J
Explanation:
GIVEN DATA:
mass of spider man is m 74 kg
vertical displacement if spider is 11 m
final displacement = 11 cos 60.6 = - 6.753 m
change in displacement is = -6.753 - (-11) = 4.25 m
gravity force act on spiderman is f = mg = 74 × 9.8 = 725.2 N
work done by gravity is 

where 180 is the angle between spiderman weight and displacement
W = -1844.513 J