An engineer or scientist is warming food in an electric grill. (a) Name a suitable electromagnetic band and explain one useful property. (b) State one possible hazard of sufficiently intense exposure to that band. (c) State the speed of this radiation in vacuum and explain whether it needs a material medium.

Question

Accepted Answer

infrared; it transfers thermal energy to absorbing surfaces; intense exposure can burn skin; vacuum speed 3.0 × 10⁸ m/s; no medium required. A suitable choice is infrared. Its usefulness is linked to how the radiation interacts with matter: it transfers thermal energy to absorbing surfaces. Naming the band without connecting a property to the proposed use is not a complete explanation. A relevant hazard is that intense exposure can burn skin. Risk depends on factors including intensity and exposure time, so a useful application does not mean every level of exposure is harmless. Like every electromagnetic band, this radiation travels at 3.0 × 10⁸ m/s in vacuum. Different bands have different wavelengths and frequencies, but they do not have different vacuum propagation speeds. Electromagnetic radiation does not require vibrating material particles to carry the disturbance. It can therefore travel through a vacuum, unlike sound, which requires a material medium and cannot propagate through empty space.

Electromagnetic radiation for warming food in an electric grill

What a complete response should do

How did this one feel?