Answered

At Westonci.ca, we provide reliable answers to your questions from a community of experts. Start exploring today! Join our platform to get reliable answers to your questions from a knowledgeable community of experts. Get quick and reliable solutions to your questions from a community of experienced experts on our platform.

A 25-gram paper cup falls from rest off the edge
of a tabletop 0.90 meter above the floor. If the
cup has 0.20 joule of kinetic energy when it hits
the floor, what is the total amount of energy
converted into internal (thermal) energy during
the cup’s fall?
(1) 0.02 J (3) 2.2 J
(2) 0.22 J (4) 220 J

Sagot :

W0lf93
So a cup falls from the table top to the ground and acquires 0.20 J of kinetic energy in the moment it hits the ground and we want to know what is the total amount of energy converted into thermal energy. While it is on the table, the cup has potential energy and the kinetic energy is 0. The potential energy of the cup is Ep=m*g*h where m=mass of the cup, g= gravitational acceleration of 9.81m/s^2 and h=height of the table. So Ep=0.025*9.81*0.9=0.220725 J. That potential energy converts into kinetic energy and into thermal energy via friction that the air is causing. So Ep=Ek+Efriction. From here: Efriction=Ep-Ek=0.220725 J-0.20J=0.020725J So the correct answer is (1) 0.02J
Thanks for using our platform. We're always here to provide accurate and up-to-date answers to all your queries. We appreciate your time. Please come back anytime for the latest information and answers to your questions. Get the answers you need at Westonci.ca. Stay informed with our latest expert advice.