To investigate the dynamics of human-robot acceptance, we carried out an experimental study with 56 adult participants and the iCub robot. Trust in the robot has been considered as a main indicator of acceptance and measured by the participants' conformation to the iCub's answers to questions on functional and social tasks characterized by perceptual and socio cognitive uncertainty. In particular, we were interested in understanding whether (i) trust in functional savvy is a prerequisite for trust in social savvy, and (ii) to what extent factors such as participants' desire for control, attitude towards social influence of robots, and imagined collaborative vs. competitive scenario, may influence their trust in the iCub. We found that participants conformed more to the iCub's answers in the functional than in the social tasks. Moreover, the few participants conforming to the iCub's answers in the social task also conformed less in the functional issues. Trust in the robot's functional savvy does not thus seem to be a prerequisite for trust in its social savvy. Finally, the examined factors did not influence the trust in iCub. Results are discussed with relation to methodology of human-robot interaction (HRI) research.