Access - Entrance to the Rijksmuseum in Amsterdam
All visitors to the Rijksmuseum are required to book a start time for their visit. However, once inside the Rijksmuseum you can stay for as long as you want during opening hours.
To help control the number of people who are in the Rijksmuseum at any one time, these start times are staggered. So when buying your entrance ticket online (recommended), you must select a specific date/start time.
Tickets are free for holders of the I Amsterdam City Card, otherwise the wheelchair user has to pay full adult price (entry is free for one companion though - so in addition to selecting your own full-price ticket, also select the "I already have a ticket/voucher" as the ticket option to obtain your free companion ticket - the free companion ticket can then be picked up at the ticket office when you arrive).
If you haven't booked your tickets in advance though (but you really really should), then you should definitely arrive EARLY in the day. The queues can be horrendously long. And as a relaxed visit can take around 3 hours (you could easily spend a whole week in the Rijksmuseum though), you really don't want to end up standing in a queue for hours later in the day - only to end up seeing the Rijksmuseum in just one very rushed hour!