The properties of the wave don't determine its speed. The properties of the medium do. You can FIND the speed by measuring the wave's frequency and wavelength.
Answer:The frequency of the echo is slightly decreased
Explanation:
Given
speed of boat 
cliff is 
away
when boat is still , suppose t is the time taken by the echo to reach observer on the boat
But as soon as boat starts moving the distance between cliff and boat decreasing and time for echo to reach observer also decreases
and we know 
therefore frequency of the echo slightly decreased.
Answer:
Explanation:
A.
Given:
Vo = 21 m/s
Vf = 0 m/s
Using equation of Motion,
Vf^2 = Vo^2 - 2aS
S = (21^2)/2 × 9.8
= 22.5 m.
B.
Given:
S = 22.5 + 21 mm
= 22.521 m
Vo = 0 m/s
Using the equation of motion,
S = Vo × t + 1/2 × a × t^2
22.521 = 0 + 1/2 × 9.8 × t^2
t^2 = (2 × 22.521)/9.8
= 4.6
t = 2.14 s
Answer:
Spring potential energy = 7.875Nm
Explanation:
<u>Given the following data;</u>
Extension, e = 15cm to meters = 15/100 = 0.15m
Spring constant, k = 350n/m
To find the force;
Force = spring constant * extension
Force = 350 * 0.15
Force = 52.5 Newton.
Now to find the spring potential energy we would use the formula below;
Spring potential energy = force * extension
Substituting into the equation, we have;
Spring potential energy = 52.5 * 0.15
<em>Spring potential energy = 7.875Nm</em>
The answer is 12,390 ft.
At first, a climber is at 12,470 <span>ft above sea level. But then, he goes down 80 ft to meet a fellow climber. So, this simply needs to be distracted:
12,470 ft - 80 ft = 12,390 ft
This is the elevation </span>above sea level at which he meet the other climber.
