Part B Test Questions And Actual
Answers.
Three boxes are pulled to the left by strings with negligible mass on a horizontal surface, as
shown above. The masses of the boxes are m1, m2, and m3, where m3>m2>m1. Friction
between the boxes and the surface is negligible. The figure below shows force diagrams for
each box. Given that m3>m2>m1, how do the force F and string tensions TA and TB compare? -
Answer Tb<ta<F
Three boxes are pulled to the left by strings with negligible mass on a horizontal surface, as
shown above. The masses of the boxes are m1, m2, and m3, where m3>m2>m1. Friction
between the boxes and the surface is negligible. The figure below shows force diagrams for
each box. Which of the following is a correct ranking of the normal forces Fn1, Fn2, and Fn3
exerted on the boxes? - Answer Fn3>Fn2>Fn1
Three boxes are pulled to the left by strings with negligible mass on a horizontal surface, as
shown above. The masses of the boxes are m1, m2, and m3, where m3>m2>m1. Friction
between the boxes and the surface is negligible. The figure below shows force diagrams for
each box. A student is trying to determine the tensions in the strings connecting the boxes. If
the acceleration of the system and the pulling force F are known, which of the following pairs of
equations could be used to find the tensions? - Answer m3a3 = Tb & m2a2 = Ta - Tb
Three boxes are pulled to the left by strings with negligible mass on a horizontal surface, as
shown above. The masses of the boxes are m1, m2, and m3, where m3>m2>m1. Friction
between the boxes and the surface is negligible. The figure below shows force diagrams for
each box. Students attach a force probe in the middle of string A to measure TA and then use a
different force probe to provide the applied force F to the box of mass m1. With the box of mass
m3 held in place by one student, a second student pulls to the left on the force probe that
provides the applied force F. As the second student pulls with a steady force, and with the boxes
remaining at rest, the following pairs of readings from the two force probes are recorded at
different times. Based on the measurements above, how do the magnitudes of the two force
quantities compare? - Answer The two quantities agree within experimental uncertainty but
do not exactly agree numerically
A hockey player uses a hockey stick to hit a puck such that the stick provides an applied force on
the puck. The puck travels for distance of 0.85m while experiencing the force from the stick. The
puck leaves the stick with a speed of 8.0m/s and travels at constant speed in a straight line
along the horizontal ice for a distance of 12m. The frictional force between the puck and the ice