A ball is projected upwards from the top of a tower with a velocity of $$50$$ $$ms-1$$ making an angle of $$30$$° with the horizontal. The height of the tower is $$70$$ m. After how many seconds from the instant of throwing will the ball reach the ground ?

Question

Infinity Learn · Accepted Answer

The vertically upward component of the velocity of projection $$=$$ $$50$$ $$sin$$ $$30$$° m $$/$$ s $$=25$$ $$ms-1If$$ t is the time taken to reach the ground, we $$haves=$$−$$u0t+12gt2or$$ $$70=$$−$$25t+1210t2or$$ $$5t2$$ $$-$$ $$25t$$ $$-70$$ $$=$$ $$0$$ so t $$=$$ $$-2s$$ or t $$=$$ $$7sHere$$, t $$=$$ $$-2s$$ is not valid.

A ball is projected upwards from the top of a tower with a velocity of 50 ms^-1 making an angle of 30° with the horizontal. The height of the tower is 70 m. After how many seconds from the instant of throwing will the ball reach the ground ?

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A ball is projected upwards from the top of a tower with a velocity of 50 ms-1 making an angle of 30° with the horizontal. The height of the tower is 70 m. After how many seconds from the instant of throwing will the ball reach the ground ?

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A ball is projected upwards from the top of a tower with a velocity of 50 ms^-1 making an angle of 30° with the horizontal. The height of the tower is 70 m. After how many seconds from the instant of throwing will the ball reach the ground ?