Science Assessment

An inventor is trying to create a device that measures the amount of energy transferred from an object by electromagnetic radiation. He needs to calibrate the instrument by finding an object that does not give off electromagnetic radiation so he can get a zero reading on his device. However, he notices that wherever he places the device, it always registers some amount of background radiation. He thinks that objects in and around his laboratory are radiating energy. What should the inventor do to isolate the device from potential sources of electromagnetic radiation?

1. He should calibrate the device in an airtight vacuum chamber because electromagnetic radiation cannot travel in a vacuum.
2. He should calibrate the device at a very low temperature (0°C) because electromagnetic radiation is only emitted by warm objects.
3. He should calibrate the device while surrounded by a protective shield, such as lead, because some substances only absorb electromagnetic radiation and do not emit electromagnetic radiation.
4. All objects give off electromagnetic radiation, so the inventor will never get a true zero reading on his device.