A beam of light, with a wavelength of 4170 Å, is shined on sodium, which has a work function (binding energy) of 4.41 × 10 –19 J. Calculate the kinetic energy and speed of the ejected electron.

A1,200 kg car is accelerated at 3.7 m/s2. what force was needed to produce this acceleration? a. 4,440 n b. 324.3 n c. 4,388 n d. 304.3 n

In a system, when potential energy decreases, then entropy also decreases. true false

An object with initial temperature 130 ∘ f is submerged in large tank of water whose temperature is 50 ∘ f . find a formula for f ( t ) , the temperature of the object after t minutes, if the cooling constant is k = − 0.2 . remember newton's law of cooling (the rate of change of temperature with respect to time is equal to k times the difference between the temperature of the object and the surrounding temperature) ! : )