Easy -1.2 This is a straightforward single-step projectile motion problem requiring only the vertical motion equation with standard SUVAT. Students need to recall that vertical displacement is zero when the particle returns to ground level, then solve 0 = ut sin(40°) - ½gt² for t. It's more routine than average A-level questions as it requires no problem-solving insight, just direct application of a memorized formula.
1 A particle is projected with speed \(15 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) at an angle of \(40 ^ { \circ }\) above the horizontal from a point on horizontal ground. Calculate the time taken for the particle to hit the ground.
1 A particle is projected with speed $15 \mathrm {~m} \mathrm {~s} ^ { - 1 }$ at an angle of $40 ^ { \circ }$ above the horizontal from a point on horizontal ground. Calculate the time taken for the particle to hit the ground.
\hfill \mbox{\textit{CAIE M2 2011 Q1 [2]}}