Which type of waves from the electromagnetic spectrum are used in heat lamps and heat sensing devices?
visible light
ultraviolet rays
radio waves
infrared waves

Infrared waves are used in heat lamps and other heat sensing devices. Infrared waves or commonly known as Infrared radiations (IR) is the type of electromagnetic radiation we encounter most in our everyday life. Heat lamps are electrical devices which emit infrared radiation.

Answer: fn = wcos50 = 38.89(9.81)(cos50) = 245.23 n