elastic force on the balloon
f = kx
here we know that
k = 115 n/m
x = 0.8 m
f = 115 n/m (0.8m) = 92 n
elastic potential energy
u = 36.8 j
by energy conservation
initial kinetic energy = final potential energy
u = ke
as we know that
by solving above equation we have
recall the equation relating an object's change in thermal energy to its change in temperature:
δq = mcδt
δq is the change in thermal energy.
m is the mass of the object.
c is the object's specific heat.
δt is the object's change in temperature.
m = 0.5 kg = 500g
δt = (7-0)⁰c = 7°c
online sources say the specific heat of silver is 0.240 j/g⁰c
substitute the terms in the equation with the given values and solve for δq:
δq = 500×0.240×7δq = 840 j
a longitudinal wave is a wave that vibrates the medium in the same direction in which the wave energy travels.
the answer would be c.