Can I play quicktime video on an ipad?

Yes.

http://www.apple.com/ipad/specs/

Video formats supported: H.264 video up to 720p, 30 frames per second, Main Profile level 3.1 with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats; MPEG-4 video, up to 2.5 Mbps, 640 by 480 pixels, 30 frames per second, Simple Profile with AAC-LC audio up to 160 Kbps per channel, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats; Motion JPEG (M-JPEG) up to 35 Mbps, 1280 by 720 pixels, 30 frames per second, audio in ulaw, PCM stereo audio in .avi file format.

I am having problems viewing a QuickTime video sent to me as an email attachment. Do I need todo something to view it? I see the QuickTime file box. When I click on it it goes into my photos but then a little error msg pops up and says unable to play this video. It stays in my photos but it just looks like a photo. Can anyone help me?