Question

If four balls A,B,C,D are projected with the same speed at angles of 15°,30°,45°and60° with the horizontal respectively , the two balls which will fall at the same place will be ?

Answer 1

Range=u²sin2Θ/g

Since they are projected with same speeds, the angles whose sin2Θ values are same will have same range

sin2(15°)=sin30°=1/2

sin2(30°)=sin60°=√3/2

sin2(45°)=sin90°=1

sin2(60°)=sin120°=√3/2

Therefore the balls B and D with projection angles 30 and 60 respectively land at the same position