Asked Dec 17, 2019

A soap film is held vertically in air and is viewed in reflected light as in Figure CQ24.14. Explain why the film appears to be dark at the top.

Figure CQ24.14
Andraw Lambart Photographw/Science Source

Image Transcriptionclose

Figure CQ24.14 Andraw Lambart Photographw/Science Source


Expert Answer

Step 1

Step 1 

The film appears dark when held vertically in air and viewed in the reflected light because of the reasons mentioned ahead.

Step 2

Step 2 

Due to gravity, the soap film tends to sag in its holder, being quite thin at the top and becoming thicker as one moves toward the bottom of the holding ring. Because light reflecting from the front surface of the film experiences a phase reversal, and light reflecting from the back surface of the film does not, the film must be a minimum of a half wavelength thicker befo...

Want to see the full answer?

See Solution

Check out a sample Q&A here.

Want to see this answer and more?

Solutions are written by subject experts who are available 24/7. Questions are typically answered within 1 hour.*

See Solution
*Response times may vary by subject and question.
Tagged in



Related Physics Q&A

Find answers to questions asked by student like you
Show more Q&A

Q: A block of mass m = 5.8 kg is pulled up a 0 = 25° incline as in Figure P4.24 with a force of magnitu...

A: Click to see the answer


Q: A 2.10 x 103 - kg pile driver is used to drive a steel I - beaminto the ground. The pile driver fall...

A: Write the expression for net-work done on the beam using work-energy theorem


Q: A 75-kg man standing on ascale in an elevator notesthat as the elevator rises, thescale reads 825 N....

A: Given thatm = 75 kgF = 825 Ng = 9.8 m/s2


Q: A boy coasts down a hill on a sled, reaching a level surface atthe bottom with a speed of 7.00 m/s. ...

A: Let the mass of the boy and the sled together be denoted by m.Let the weight of the boy and sled tog...


Q: A bag of sugar weighs 5.00 lb on Earth. What would it weigh innewtons on the Moon, where the free-fa...

A: Click to see the answer


Q: What is a radiation curve? explain with graph.

A:  Radiation curve can be defined as the curve that is drawn between the intensity of the thermal radi...


Q: A 3.00-kg block starts from rest at the top of a 30.0° inclineand slides 2.00 m down the incline in ...

A: part A:


Q: A 33 kHz soundwave travels in air at v=355 m/s What is the temperature of the air through which it t...

A: What is the velocity and wavelength?   Given data:Frequency of the soundwave, f  = 33 kHz = 33000 Hz...


Q: A student throws a heavy red ball horizontally from a balconyof a tall building with an initial spee...

A: In both cases when the ball is thrown horizontally and dropped down vertically, the initial vertical...