Question

What is the least amount of time required for a given point on this wave to move from y = 0 to y = 12cm?

Answer 1

Time t = ?

When wave is moving from y = 0  to y =12 cm

By using the formula,

y = 15cos [(π/12) t)] = 0,

cos [(π/12) t)] = 0 = cos (π/2), so, 

(π/12)t = π/2,

t = (π/2) (12/π) 

t = 12/2

t = 6 sec

so 6 sec is the least amount of time required