Answer:9.75 m/s
Explanation:
Given
Length of ladder 
Foot the ladder is moving away with speed of 
From diagram
------1
at 


Now differentiating equation 1 w.r.t time




negative indicates distance is decreasing with time
60,000 meters. no explanation
Answer:
The frequency of the wave is 5.0Hz
Explanation:
The frequency of a wave is the number of oscillations or revolutions made in a second.
Answer:
a) α = 1.875 
b) t = 8 s
Explanation:
Given:
ω1 = 0 
ω2 = 15 
theta (angular displacement) = 60 rad
*side note: you can replace regular, linear variables in kinematic equations with angular variables (must entirely replace equations with angular variables)*
a) α = ?
(ω2)^2 = (ω1)^2 + 2α(theta)
=
+ 2(α)(60)
225 = 120α
α = 1.875 
b)
α = (ω2-ω1)/t
t = (ω2-ω1)/α = (15-0)/1.875 = 8
t = 8 s