a stone is thrown horizontally with speed 15m/s from the top of a cliff 30 metres high. construct a diagram showing the positions of the particle at 0.5 second intervals. Estimate the distance of the stone from the thrower when it is level with the floor of the cliff and the time it takes to fall.

Question

abmon98 · Answer

figure how long the object is in the air it depends on the vertical motion 
s=1/2gt^2
30=1/2(10)t^2
(60/10)^1/2=2.45
we need to figure how far the object it travels, no force of gravity is acting in the x direction
s=ut
s=15*2.45
s=36.75 m
this is my working but the distance is incorrect, its written at the back of my book as 47 m

abmon98 · Answer

@Abhisar can you check out this question?

mrnood · Answer

$$s=\frac{ g t ^{2} }{ 2 }$$

$$30= \frac{ 9.8 t ^{2} }{ 2 }$$

$$\frac{ 60 }{ 9.8 } =t ^{2}$$

t=2.47 s

So horizontal distance = 15* 2.47 = 37 m

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