Complete Question
You are performing a double slit experiment very similar to the one from DL by shining a laser on two nattow slits spaced
meters apart. However, by placing a piece of crystal in one of the slits, you are able to make it so that the rays of light that travel through the two slits are Ï out of phase with each other (that is to say, Ao,- ). If you observe that on a screen placed 4 meters from the two slits that the distance between the bright spot closest to center of the pattern is 1.5 cm, what is the wavelength of the laser?
Answer:
The wavelength is 
Explanation:
From the question we are told that
The distance of slit separation is
The distance of the screen is 
The distance between the bright spot closest to the center of the interference is 
Generally the width of the central maximum fringe produced is mathematically represented as

=> 
=> 
=> 
Answer:
240 ohms
Explanation:
From Ohms law we deduce that V=IR and making R the subject of the formula then R=V/I where R is resistance, I is current and V is coltage across. Substituting 120 V for V and 0.5 A for A then
R=120/0.5=240 Ohms
Alternatively, resistance is equal to voltage squared divided by watts hence 
The height above the ground from where the skier start is 11.5 m.
<h3>
Conservation of energy</h3>
The height above the ground from where the skier start is determined by applying the principle of conservation of energy as shown below;
P.E = K.E
mgh = ¹/₂mv²
gh = ¹/₂v²

Thus, the height above the ground from where the skier start is 11.5 m.
Learn more about conservation of energy here: brainly.com/question/166559