Standard +0.3 This is a straightforward projectiles question requiring students to find when speed equals 12 m/s using the standard formula v² = u² - 2g(s_y) or component methods, then double the time to maximum speed. It's slightly above average difficulty due to requiring the speed condition rather than just range/height, but the method is standard and well-practiced in M2 courses.
A small ball is projected with speed \(16 \text{ ms}^{-1}\) at an angle of \(45°\) above the horizontal from a point on horizontal ground. Calculate the period of time, before the ball lands, for which the speed of the ball is less than \(12 \text{ ms}^{-1}\). [4]
A small ball is projected with speed $16 \text{ ms}^{-1}$ at an angle of $45°$ above the horizontal from a point on horizontal ground. Calculate the period of time, before the ball lands, for which the speed of the ball is less than $12 \text{ ms}^{-1}$. [4]
\hfill \mbox{\textit{CAIE M2 2016 Q1 [4]}}