R01e（EnePick）

EnePick

PURPOSE

EnePick is effective when teaching the followings

[energy conversion between light and electricity]

[efficiency of energy conversion]

[electric circuit]

TARGET

Elementary school students (4th, 6th Grade)

Junior high school Students (8th, 9th Grade)

CATEGORY

Physics, Monozukuri(Science craft)

HOW TO MAKE

All parts are shown in Fig.1.

(1) Red LED (OptoSupply, OSHR5111A) ... 2

(2) Capacitor (220 μF, 16V) ... 1

(3) Resistor (2kΩ, 1/6W) ... 1

(4) Vinyl tube (Outer diameter: 12mm, Inner diameter:10mm, length:45mm) ...1 piece

(5) Toalon tube (Outer diameter: 16mm, Inner diameter:12mm, length:8mm) ...2 pieces

(6) OHP film (35 X 10 mm ) ...1

(7) OHP film (20 X 10 mm ) ...1

(8) Aluminum tape (35 X 10 mm ) ...2

(Circuit)

The parts are assembled as shown in Fig.2(A).

The circuit diagram is shown in Fig.2(B).

Store the (circuit and switch) in a Vinyl tube as shown in Fig.3.

HOW TO USE

Charging:

Direct the LEDs of EnePick to the light source as shown in Fig.4.

The 2 LEDs are connected in series,

And, The terminal voltage of the condenser is 3.5V.

When a LC projector is used as a light source, it will take 10seconds to charge the condenser. (cf. Fig.5)

When the sun is used as a light source, it will take 1 or 2 minutes to charge the condenser.(cf. Fig.6)

Discharging:

Push the switch.

One of the two LEDs is connected to the condenser. (cf. Fig.2(B))

One LED emits light for several seconds as shown in Fig.7.

There is large difference between charging time and discharging time.

It helps students to recognize the energy loss during energy conversion processes.

REFERENCES

M.Watanabe and M.Kamata, "A Tool for Helping Students to Realize Energy Conversion between Light and Electricity", Jouornal of the Physics Education Society of Japan, Vol. 59, pp.9-13 (2011) (written in Japanese)

Masahiro Kamata and Yuna Tamamura,"Tiny tool converts light to electricity", PHYSICS EDUCATION, 45, 224-226 (2010)