A) 50 cm
B) 10000 cm/s
Explanation
Step 1
A)
If you know the distance between nodes and antinodes then use this equation:
[tex]\begin{gathered} \frac{\lambda}{2}=D \\ \text{where}\lambda\text{ is the wavelength} \\ D\text{ is the distance betw}een\text{ nodes} \end{gathered}[/tex]then, let
[tex]D=\text{ 25 cm }[/tex]now, replace to find the wavelength
[tex]\begin{gathered} \frac{\lambda}{2}=25 \\ \text{Multiply both sides by 2} \\ \frac{\lambda}{2}\cdot2=25\cdot2 \\ \lambda=50\text{ Cm} \end{gathered}[/tex]so, the wavelength is
A) 50 cm
Step 2
The speed of a wave can be found using the equation
[tex]v=\lambda f[/tex]or velocity = wavelength x frequency,
then,let
[tex]\begin{gathered} \lambda=50\text{ cm} \\ f=200\text{ Hz} \end{gathered}[/tex]replace and evaluate
[tex]\begin{gathered} v=\lambda f \\ v=50\text{ cm }\cdot200\text{ HZ} \\ v=10000\text{ }\frac{\text{cm}}{s} \end{gathered}[/tex]so
B) 10000 cm/s
I hope this helps you