You are in closed room somehwere on Earth. You have no compas, gyroscope or GPS. No TV, phone, FAX, emil, computer, internet, or cell. No cable no external connections with outside networks. However you have electricity the regular network and a lab with all sort of electric equipment, and chemical equipment. But no compas or magnetic needles, or magnetic powerd, or magnetic materials, tapes, etc. Just electricity, electronics, chemistry. You cannot see outside, you cannot talk to anybody, no windows or doors. Describe a way to find out what direction is North in this room.

4 answers

Good question. You can get the latitude with a Foucault pendulum (and a clock to figure out how much the plane of oscillation rotates in 24 hours.) But it won't tell you where North is.

You could use an electromagetic method to MAKE a compass needle, or just flip a wire coil 180 degrees and measure the induced emf with electronics. When the axis of the flip is aligned with the Earth's magnetic field, there will be no emf pulse.

I am curious to hear what other ways people (including your teacher) can come up with.. particularly any that use chemistry.
Someone else looking for solution to Dr. Ludu's assignment for tomorrow! Ha!
Why does Ludu have to be so difficult! Grrr!
you can create a compass by using whats in the room. you can brake off a piece of wire about an inch or two long and magnetize it with the use of electricity and wires. you will need to mark one end as this is the end you will start your magnetizing from and it will be your N pole. you can use a bowl of some sorts to hold water that you can float something on like a piece of sponge or small wood block. take the magnetized wire (preferably a single strand about the size of a hair) and place it onto the material suspended in the water. that is your compass; the wire is the needle and is magnetized to have a north and south pole. the needle will point to a north/south direction.