Box in a Truck Bed 2#

A sedan is approaching a stop-light as it drives down the road moving in the negative direction. There is a box in the back of the sedan which, according to the driver, stays IN PLACE the whole time until the sedan has come to a complete stop.

Part 1#

What type of friction is acting the box? From the perspective of a pedestrian watching the sedan drive past, is the work by the friction force on the box positive, negative, or zero?

Answer Section#

  • Kinetic friction, positive work

  • Kinetic friction, negative work

  • Kinetic friction, zero work

  • Static friction, positive work

  • Static friction, negative work

  • Static friction, zero work

Attribution#

Problem is from the OpenStax University Physics Volume 2 textbook, licensed under the CC-BY 4.0 license.
Image representing the Creative Commons 4.0 BY license.