<span>A van is traveling on a road at a speed of 55 km/h relative to a
stationary observer on the side of the road. A girl sitting near the
driver of the van throws a paper airplane to a boy at the back of the
van with a speed of 2 km/h relative to the girl, the boy, and the van.
The speed of the paper airplane, relative to the same stationary observer
on the side of the road, is (55 - 2) = 53 km/h. No rounding is necessary.</span>
Answer:
- path differnce = 2.18*10^-6
- 1538 lines
Explanation:
- The path difference for the waves that produce the pattern of diffraction, is given by the following formula:
(1)
d: separation between slits = 0.50mm = 0.50*10^-3 m
θ: angle of a diffraction = 0.25°
Then, the path difference is:

- The maximum number of bright lines are calculated by using the following formula:
(2)
m: order of the bright
λ: wavelength = 650nm
The maximum bright is calculated for an angle of 90°:

The maxium number of bright lines are twice the previous result, that is, 1538 lines
Answer:
I'll try to help which grade are you?