Can someone please help me quick :(
A toy spring with a spring constant of 6.4 N/m has a relaxed length of 20.0 cm. When a ball is attached to the end of the spring and allowed to come to rest, the vertical length of the spring is 75.0 cm. What is the elastic potential energy stored in the spring

PE = 0.968  J

Explanation:

the formula for potential elastic energy is

PE = kx^2/2

k = spring constant 6.4 N/m

x = displacement = 75 - 20 = 55 cm = 0.55m

plug these values into the equation

PE = 6.4(0.55)^2 / 2

PE = 0.968  J

answer: option c.

explanation:

d₁ = displacement of tern from arctic to antarctic = 11000 miles

d₂ = displacement of tern from antarctic to arctic =   - 11000 miles

d = total displacement for the journey

total displacement for the journey is given as

d = d₁ + d₂

d = 11000 + (-11000)

d = 0 miles

t₁ = time of travel from arctic to antarctic = 3 months = 3 x 30 days = 90 days

t₂ = time of travel from antarctic to arctic = 3 months = 3 x 30 days = 90 days

t = total time of travel

total time of travel is given as

t = t₁ + t₂

t = 90 + 90

t = 180 days

average velocity is given as

average velocity = total displacement/ total time

v = d/t

v = 0/180

v = 0 miles/day