The length of a wave so, therefore its D.
Answer:
I believe the answer is A and D.
I am unsure of C.
Answer:
A boat travels for three hours with a... A boat travels for three hours with a current of 3 mph and then returns the same distance against the current in four hours. What is the boat's speed in still water?
Explanation:
I think it’s c because the other ones are just options not facts
Explanation:
Given that,
Work done to stretch the spring, W = 130 J
Distance, x = 0.1 m
(a) We know that work done in stretching the spring is as follows :
![W=\dfrac{1}{2}kx^2\\\\k=\dfrac{2W}{x^2}\\\\k=\dfrac{2\times 130}{(0.1)^2}\\\\k=26000\ N/m](https://tex.z-dn.net/?f=W%3D%5Cdfrac%7B1%7D%7B2%7Dkx%5E2%5C%5C%5C%5Ck%3D%5Cdfrac%7B2W%7D%7Bx%5E2%7D%5C%5C%5C%5Ck%3D%5Cdfrac%7B2%5Ctimes%20130%7D%7B%280.1%29%5E2%7D%5C%5C%5C%5Ck%3D26000%5C%20N%2Fm)
(b) If additional distance is 0.1 m i.e. x = 0.1 + 0.1 = 0.2 m
So,
![W=\dfrac{1}{2}kx^2\\\\W=\dfrac{1}{2}\times 26000\times 0.2^2\\\\W=520\ J](https://tex.z-dn.net/?f=W%3D%5Cdfrac%7B1%7D%7B2%7Dkx%5E2%5C%5C%5C%5CW%3D%5Cdfrac%7B1%7D%7B2%7D%5Ctimes%2026000%5Ctimes%200.2%5E2%5C%5C%5C%5CW%3D520%5C%20J)
So, the new work is more than 130 J.