Problem 1

A ball is launched horizontally from height

h=20\,\mathrm m

u=15\,\mathrm{m/s}

above level ground. Neglect air resistance and take

g=10\,\mathrm{m/s^2}

. Horizontal motion is uniform and vertical acceleration is downward. (a) Find the first requested quantity. (b) Find the second quantity. (c) Determine the final result and check its (a) Find the flight time. (b) Find the horizontal range. (c) Find the impact speed and its angle below horizontal.

problems.proof.stepOf

problems.proof.prevStep problems.proof.nextStep

x=ut=30\,\mathrm m

problems.proof.analysis

This equation expresses the physical law governing the system. It incorporates the stated constraint rather than treating the relevant quantities as independent.

problems.proof.pitfall. Check the sign convention and physical case carefully; do not use a formula for a different motion or geometry.