What is the energy output of a light source in J/s (joules per second) if it produces 324 photons per second, and these photons have a wavelength of 143 nm? c = 2.998 x 108 m/s. h = 6.63 x 10-34 J-s. a) The energy output is 1.39e-18 J/s. b) The energy output is 4.50e-16 J/s. c) The energy output is 2.33e+20 J/s. d) The energy output is 4.29e-21 J/s. e) The energy output is 3.07e-38 J/s.

If an object with an initial temperature of 300 k increases its temperature by 1°c every minute, by how many degrees fahrenheit will its temperature have increased in 10 minutes? (a) 6°f (b) 10°f (c) 18°f (d) 30°f

Asled is being held at rest on a slope that makes an angle θ with the horizontal. after the sled is released, it slidesa distance d1 down the slope and then covers the distance d2 alongthe horizontal terrain before stopping. find the coefficient ofkinetic friction μk between the sled and the ground, assumingthat it is constant throughout the trip. find the coefficient of kinetic frictionμk. express your answer in terms of someor all of the variables d1, d2, and θ.

Thermal radiation gets its name because