﻿ During volcanic eruption chunks of solid rock are blasted out of the volcano. (a) At what initial speed would a volcanic object have to be ejected at 37° to the horizontal from the vent A in order to fall at B as shown in fig. (b) What is the time of flight? (g = 9.8 m/s2)                                                    : Kaysons Education

# During Volcanic Eruption Chunks Of Solid Rock Are Blasted Out Of The Volcano. (a) At What Initial Speed Would A Volcanic Object Have To Be Ejected At 37° To The Horizontal From The Vent A in Order To Fall At B as Shown In Fig. (b) What Is The Time Of Flight? (g = 9.8 M/s2)

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## Question

### Solution

Correct option is

(255 m/s, 46 s)

Taking the point A as origin, with upward direction of motion positive and using the equation,

For horizontal motion:       x = u cos θ × t                          …(1)

And for vertical motion:

Substituting t from Eqn.  (1) in (2),

(b) substituting the above value of u in Eqn. (1),

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