It is motion sickness, you r not getting it in train because its moving on a constant gradient no ups and downs,
In boat if waves are bigger and boat goes on unpredictable ups and downs u will get it..
Closed spaces unable to visualise out side can cause giddiness as well,
In bus or car if you sit on window side and see outside you may not get giddiness..
Answered2020-08-27 14:30:42
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