SAT Subject Physics Practice Question 110: Answer and Explanation
5. A string, fixed at both ends, supports a standing wave with a total of 4 nodes. If the length of the string is 6 m, what is the wavelength of the wave?
A. 0.67 m
B. 1.2 m
C. 1.5 m
D. 3 m
E. 4 m
Correct Answer: E
The distance between successive nodes is always equal to λ. If a standing wave on a string fixed at both ends has a total of 4 nodes, the string must have a length L equal to 3(λ). If L = 6 m, then λ must equal 4 m.