How many collision domains in a 24 port switch?

1 broadcast domain and 12 collision domains

12A switch creates separate collision domains for each port.

It depends on the switch, all switches are different. Some may have 16 while others may have 24.

there are 8, 16, 48 ports in network switch

A hub contains a single collision domain and a single broadcast domain, regardless of the number of ports on the hub.