A projectile is given an initial velocity of $$5$$ $$m/s$$ at an angle $$30$$° below horizontal from the top of a building $$25$$ m high. Find (a) the time after which it hits the ground; (b) the distance from the building where it strikes the ground. (g$$ $$=$$ $$10$$ $$m/s2)

Question

Infinity Learn · Accepted Answer

The projectile is thrown from point O and lands at point A on the ground.From O to A : sy $$=$$ $$-25m$$, uy $$=$$ $$-5$$ $$sin30o$$ $$=$$ $$-2.5m$$ $$/$$ s (negative$$ because vertical component acts $$downwards)(a) We have $$ay=$$−$$g=$$−$$10m/s2$$ $$sy=uyt+(1/2)ayt2$$−$$25=$$−$$2.5t$$−(1/2)(10)t2So$$, therefore $$10t2$$ $$+$$ $$5t$$ $$-$$ $$50$$ $$=$$ $$0$$. On solving, we get is t $$=$$ $$2s$$, $$-2.5$$ s.The relevant time is $$2s$$.$$(b) $$sx=uxt=5cos$$⁡$$30$$∘$$2=53m$$.

A projectile is given an initial velocity of 5 m/s at an angle 30° below horizontal from the top of a building 25 m high. Find (a) the time after which it hits the ground; (b) the distance from the building where it strikes the ground. (g = 10 m/s²)

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A projectile is given an initial velocity of 5 m/s at an angle 30° below horizontal from the top of a building 25 m high. Find (a) the time after which it hits the ground; (b) the distance from the building where it strikes the ground. (g = 10 m/s2)

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A projectile is given an initial velocity of 5 m/s at an angle 30° below horizontal from the top of a building 25 m high. Find (a) the time after which it hits the ground; (b) the distance from the building where it strikes the ground. (g = 10 m/s²)