Question
Integrated Concepts: A 2.50-kg fireworks shell is fired straight up from a mortar and reaches a height of 110 m. (a) Neglecting air resistance (a poor assumption, but we will make it for this example), calculate the shell’s velocity when it leaves the mortar. (b) The mortar itself is a tube 0.450 m long. Calculate the average acceleration of the shell in the tube as it goes from zero to the velocity found in (a). (c) What is the average force on the shell in the mortar? Express your answer in newtons and as a ratio to the weight of the shell.

a) $46.4 \textrm{ m/s}$

b) $2.40 \times 10^3 \textrm{ m/s}^2$

c) $5.99 \times 10^3 \textrm{ N}$, which is 244 times the shell's weight. (Note that 245 is written in the video, but as the calculator screenshot shows, this should be rounded to 244.)

Solution Video