A boy throws a ball upwards with velocity $$v0$$ $$=$$ $$20$$ $$m/s$$. The wind imparts a horizontal acceleration of $$4$$ $$m/s2$$ to the left. The angle θ with the vertical at which the ball must be thrown, so that the ball returns to the boy’s hand is : (g$$ $$=$$ $$10$$ $$m/s2)

Question

A boy throws a ball upwards with velocity $$v0$$ $$=$$ $$20$$ $$m/s$$. The wind imparts a horizontal acceleration of $$4$$ $$m/s2$$ to the left. The angle θ with the vertical at which the ball must be thrown, so that the ball returns to the boy’s hand is : (g$$ $$=$$ $$10$$ $$m/s2)

Infinity Learn · Accepted Answer

$$vy=v0cos$$⁡θ$$=20cos$$⁡θ$$vx=v0sin$$⁡θ$$=20sin$$⁡θTime of flight of the ball is :$$T=2vyg=40cos$$⁡θ$$10=4cos$$⁡θ...(i)In$$ this time displacement of ball in horizontal direction should also be zero,i.e.,  $$0=vxT$$−$$12axT2This$$ gives, $$T=2vxax=(20sin$$⁡θ$$)24=$$ $$10$$ $$sin$$ θ .....$$(ii)From$$ eqn. $$(i) and eqn. $$(ii)4$$ $$cos$$θ $$=$$ $$10$$ $$sin$$ θ∴$$tan$$⁡θ$$=410=0.4$$

A boy throws a ball upwards with velocity v₀ = 20 m/s. The wind imparts a horizontal acceleration of 4 m/s² to the left. The angle $θ$ with the vertical at which the ball must be thrown, so that the ball returns to the boy’s hand is : (g = 10 m/s²)

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A boy throws a ball upwards with velocity v0 = 20 m/s. The wind imparts a horizontal acceleration of 4 m/s2 to the left. The angle θ with the vertical at which the ball must be thrown, so that the ball returns to the boy’s hand is : (g = 10 m/s2)

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A boy throws a ball upwards with velocity v₀ = 20 m/s. The wind imparts a horizontal acceleration of 4 m/s² to the left. The angle $θ$ with the vertical at which the ball must be thrown, so that the ball returns to the boy’s hand is : (g = 10 m/s²)