Constructing an Energy-Collecting Apparatus for Physics Experiment

[dragos]

The purpose of this experiment is to construct an energy-collecting apparatus to concentrate as much energy from a provided 250 Watt heat lamp as possible. This energy is to be used to heat a mass of water. (the water will be given at a fixed temperature in a 35 mm film canister).
The heat lamp will be positioned 1.2m above the floor and the construction of the apparatus can't be higher then 0.9m, and the film canister should be easily put in the apparatus and taken out.
Anyone have any ideas?
please help...

 

[berkeman]

A parabolic reflector (or two...) comes to mind

 

[dragos]

parabolic reflector

ic.. but where should i position the parabolic reflector, since i can't do anything to the lamp given in this experiment.
-as i understand I am supposed to build some kinda box that will attract as much heat as possible in order to heat the water.

 

[andrevdh]

The reflector should be below the canister, which must be a bit further away from its focus. Since you know the dimensions of the setup you can experiment with a visible source (candle?) to locate the optimum point.