This timer is useful for students to develop basic understanding of constant speed, acceleration and deacceleration. It operates on 12V a.c. and is therefore quite safe for work by students in the dynamics lab. This timer has an electromagnet with spring loaded, striker which strikes the paper tape drawn through guides. It is supplied along with a tape roll and carbon discs. Dots are spaced at 1/50 or 1/60 second intervals depending on a mains frequency.
