Q1. A person eats a dessert that contains 260 calories one. The skin temperature of this individual is 36 degree Celsius and that of her surroundings is 21 degrees Celsius. The emissivity of her skin is 0.75 and its surface area is 1.3 square. How much time would it take for her to emit a net radiant energy from her body that is equal to energy contained in this dessert?
Q2. The alpha line in the Balmer series of the hydrogen spectrum consists of light having a wavelength of 6.56 ×10-7 meter. Compute the frequency of this light. [Demonstrate all work,including the equation and substitution with units.]
Q3. As your hand moves back and forth to make longitudinal pulses in a spiral spring, your hand completes 3.75 back-and-forth cycles every 5.82 s. The velocity of the pulse in the spring is 1.25 cm/s. What is wavelength?
Respond in units of m