iPad Doesn't Render H.264 Video with HTML5

I have some H.264-encoded videos which render in HTML5 correctly in the web browser, but do not render correctly on the iPad. When I use a H.264 video I downloaded off the internet, my video renders correctly on the iPad, so it is not an HTML problem.

Here is the ffmpeg info about my videos --

My original .mov video:

Seems stream 1 codec frame rate differs from container frame rate: 6000.00 (6000/1) -> 30.00 (30/1)

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'a_video.mp4':

Metadata:

major_brand     : qt  
minor_version   : 537199360
compatible_brands: qt  

Duration: 00:00:42.74, start: 0.000000, bitrate: 220 kb/s

Stream #0.0(eng): Audio: aac, 44100 Hz, stereo, s16, 94 kb/s
Stream #0.1(eng): Video: h264, yuv420p, 762x464, 122 kb/s, 30 fps, 30 tbr, 3k tbn, 6k tbc

After using Handbrake to convert my .mov to a mp4, yet doesn't render on the iPad:

Seems stream 0 codec frame rate differs from container frame rate: 180000.00 (180000/1) -> 29.97 (30000/1001)

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'a_video.m4v':

Metadata:

major_brand     : mp42  
minor_version   : 0
compatible_brands: mp42isomavc1  
encoder: HandBrake 0.9.5 2011010300  

Duration: 00:00:42.77, start: 0.000000, bitrate: 169 kb/s

Stream #0.0(und): Video: h264, yuv420p, 752x464 [PAR 381:376 DAR 381:232], 35 kb/s, PAR 145161:141376 DAR 145161:87232, 29.97 fps, 29.97 tbr, 90k tbn, 180k tbc
Stream #0.1(eng): Audio: aac, 44100 Hz, stereo, s16, 128 kb/s

Here is a .mp4 I found online which does render on the iPad:

Seems stream 1 codec frame rate differs from container frame rate: 180000.00 (180000/1) -> 25.00 (25/1)

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'a_video_3_emu.mp4':

Metadata: major_br