If two point sources that create circular waves are moved closer together, what happens to the spacing between the nodal and anti-nodal lines? a. the spacing increases. c. the spacing stays the same. b. the spacing decreases. d. none of the above.

The distance between the sources of a two point surface interference determines the number of lines that can be created for the nodal and anti-nodal lines. When the sources are moved closer together, the number of lines becomes minimal. Thus, the spaces between the lines become bigger. The answer to this item is letter A. The spacing increases. 

initial speed when it is dropped is 150 ft/s

now at the same moment the acceleration due to gravity is perpendicular to its velocity

so as we know that

now we have centripetal acceleration a = 32 ft/s^2 as its perpendicular to velocity

while tangential acceleration at the same moment will be zero

so

now radius of curvature is given as

so the radius of curvature just after it is dropped is 703.125 ft

the ima (higher than 1m) will be greater than the ima with the height of 1m.