An object of mass of 2.0 kg hangs from an ideal massless spring with a spring constant of 50 N/m. An oscillating force F = (4.8 N) cos(3.0 rad/s)t is applied to the object.
What is the amplitude of the resulting oscillations? You can neglect damping.
A) 2.4 m B) 0.30 m C) 0.15 m D) 1.6 m E) 0.80 m
Question 2
You may have noticed that when you get out of a swimming pool and stand dripping wet in a light breeze, you feel much colder than you feel after you dry off. Why is this?
A) The moisture on your skin has good thermal conductivity.
B) Water has a relatively large heat capacity.
C) This is a purely psychological effect resulting from the way in which sensory nerves in the skin are stimulated.
D) The water on your skin is colder than the surrounding air.
E) 540 calories of heat are required to evaporate each gram of water from your skin, and most of this heat flows out of your body.