I'm looking to produce a pure sound on one frequency to be played via a timer to come on at intervals over a six week period. this is for an undergrad dissertation. would an arduino work and could it be fitted to a timer that would turn the sound on remotely? with thanks
Yes, but you have some design decisions to make:
Sleep or no sleep
You need to decide if you want the Arduino in those 6 weeks to sleep (using less power), or be fully active all the time. The latter is simpler, but it will use some current during those 6 weeks, to be active for a short time.
You can use a timer, however, I doubt if the timer can handle a long period of 6 weeks. In case you want to sleep, you need to store a counter each time the timer elapses and store it in EEPROM in case you want to have the Arduino in sleep mode, or in a variable when you do not want the Arduino to sleep.
Alternatively, you can use a RTC to set an alarm, and use the alarm to either wake up the Arduino (using a GPIO pin to be HIGH/LOW), or activate a function or timer.
Also instead of the timer, you can use a big delay (sleep function), but only if you want the Arduino to never sleep.
Check if the accuracy is enough in all cases.
For the buzzer, you can easily use an external component. There are plenty of examples how to control this using a frequency and time.