## A4 Laboratory Experiments

A.4.1. Rotating tables

The experiments described throughout this text come to life when they are carried out live, either in demonstration mode in front of a class or in a laboratory setting in which the students are actively involved. Indeed a subset of the experiments form the basis of laboratory-based, hands-on teaching at both undergraduate and graduate level at MIT. As mentioned in Section 0.1, the experiments have been chosen not only for their relevance to the concepts under discussion, but also for their transparency and simplicity. They are not difficult to carry out and "work" most, if not every, time. The key piece of equipment required is a turntable (capable of rotating at speeds between 1 and 30 rpm) on which the experiment is placed and viewed from above by a co-rotating camera. We have found it convenient to place the turntable on a mobile cart (see Fig. A.1) equipped with a water tank and assorted materials such as ice buckets, cans, beakers, dyes, and so on. The cart can be used to transport the equipment and as a platform to carry out the experiment.

More details about the equipment required to carry out these experiments,

FIGURE A.1. A turntable on a mobile cart equipped with a water storage tank and pump, power supply, and monitor. A tank filled with water can be seen with an ice bucket in the middle, seated on the turntable, and viewed through a co-rotating overhead camera.

including turntables and fluid carts, can be obtained from Professor John Marshall at MIT.

Measurement of table rotation rates

The rotation rate can be expressed in terms of period, revolutions per minute, or units of 'f,' as described below and set out in Table A.1:

1. The angular velocity of the tank, Q , in radians per second

2. The Coriolis parameter (f) defined as f = 2Q

3. The period of one revolution of the tank is t = 2n/Q

4. Revolutions per minute, rpm = 60/t

TABLE A.1. Various measure of rotation rates. If Q is the rate of rotation of the tank in radians per second, then the period of rotation is r^k = 2n/ Q s. Thus if Q = 1, Ttank = 2n s.