Category Archives: Classroom

God’s Not Dead

I watch “God’s Not Dead” on DVD yesterday. Usually, I do not write movie review. This is an exception.

A movie for evangelism?

If this is a movie to show the redemptive love of Christ, it failed miserably. Bringing in TV celebrity from Duck Dynasty to talk about their faith looked like an odd marketing endorsement than sincere personal testimony of his own faith. The reporter always appeared angry, rude, and had her own syndical agenda towards anyone who called himself Christian. Do journalists really behave like that in an unprofessional manner?

Stereotyping universities are hostile

Do professors in a university really act like that in the classroom? I highly doubt any creditable university professor will force any students to sign a note to declare, “God is Dead” in the beginning of a course. Moreover, I doubt any professor will yell and manhandle a student when he disagrees with his argument. If I do that with my students, I would be dismissed in no time.

Stereotyping Chinese student

I do not know why the director had to stereotype the Chinese student was a nerd and always wore a tie to class. I have not seen any Chinese students wear a tie to class during my teaching career unless they are giving a presentation or going to an interview. To make matter worse, the Chinese student spoke Cantonese (a dialect of the south) when he was talking to his father, but the father spoke Mandarin (the Beijing dialect of the north). These are two totally different dialects from two vastly different geographical regions. Do the director not expect any Chinese viewers to question the inconsistency? Can they pay more attention to detail?

Stereotyping Muslim families

Why do the producer and the director have to demonize the Muslim family? They obvious do not agree with the Muslim faith. They do not need to demonize the Muslim father was an angry, paranoid, violent tyrant who would beat up his daughter when she chose to be a Christian.

Stereotyping all non-believers

The director portrayed all the professors in the university as arrogant, self-absorbed academics love drinking red wine. They have no problem to demean young females when she let the red wine spoil in the trunk of the car. I highly doubt that many professors, especially female professors, treat a female student that way.

I can write more about why I do not like the movie, but I better draw a conclusion. I doubt God’s Not Dead will bring anyone closer to Christ. It is not even good entertainment.


Noah, the Flood and Calculus

I saw the trailer of the movie Noah. It inspired me to ask my students in my calculus class a question as a bonus assignment.

If it rained for forty days and forty nights, the water filled up to the peak of Mount Ararat, how much water fell on earth by using the disk method of calculating volume of revolution in calculus.

Some of the equations may not display correctly on the browser.

Here are the assumptions and numbers:

The earth is an ellipsoid with an equatorial radius of a=6378.1 km and polar radius of b=6356.8 km.

Mount Ararat has a height of 5.137 km.

Here is the solution:

Equation of an ellipse: x^2/a^2 +y^2/b^2 =1 or y=b/a √(a^2-x^2 )


dV=πy^2 dx, ∴V=2π∫_0^a▒b^2/a^2 (a^2-x^2 )dx

I will not type in all the detail of the calculation,

for a_2= the radius of the earth plus the height of Mount Ararat,

and a_1 = the radius of the earth,

volume of water should be approximately 2.623×10^9 km3 or 2.623×10^18 m3

The mass of the water should be approximately 2.623×10^21 kg.

For forty days and forty nights, it is a total of 960 hours, the rate of rain fall is 535.1 cm/hour or 8.9 cm/min.

Volume of water coming down from heaven is 2.732×10^15 m3/hour.

Noah does not need an ark. He needs a submarine!