Answer

Verified

427.2k+ views

**Hint:**after the volcanic eruption the rocks fly away making some angle with the horizontal and there is no external force acting on the system and the only force acting on the system is the force of gravity acting downwards and so there is constant acceleration in he downward direction, so, this is an example of projectile motion.

**Complete step by step answer:**

A- For projectile motion,

Horizontal component of velocity,

$

{{u}_{x}}=u\cos \theta \\

\implies {{u}_{x}}=u\cos 35 \\

\implies {{u}_{x}}=0.81u \\

$

Vertical component of initial velocity,

$

{{u}_{y}}=u\sin \theta \\

\implies {{u}_{y}}=u\sin 35 \\

\implies {{u}_{y}}=0.57u \\

$

There is no acceleration in horizontal direction, so horizontal velocity remains constant throughout the motion.

For projectile motion v is given by formula, \[v=\dfrac{x}{\cos \theta }\sqrt{\dfrac{g}{2(x\tan \theta -y)}}\]

Here y=-3300 m

Also, X= 9400 m

So,

\[\begin{align}

& v=\dfrac{9400}{\cos 35}\sqrt{\dfrac{9.8}{2(9400\times \tan 35+3300)}} \\

& v=255.5m{{s}^{-1}} \\

\end{align}\]

B- we have found the initial velocity and now we need to find the time, we can use the formula

\[t=\dfrac{x}{{{u}_{x}}}=\dfrac{x}{v\cos 35}=\dfrac{9400}{255.5\times \cos 35}=45s\]

C-Air resistance will be negligible but to achieve the same height in presence of such resistance we need higher initial velocity.

**Note:**

The value of y is taken negative, although it is height and that is distance and we know distance can never be negative we had taken the origin at the point from where the rock shoots and so while using newton’s equation of motion the distance comes out to be negative

Recently Updated Pages

How many sigma and pi bonds are present in HCequiv class 11 chemistry CBSE

Mark and label the given geoinformation on the outline class 11 social science CBSE

When people say No pun intended what does that mea class 8 english CBSE

Name the states which share their boundary with Indias class 9 social science CBSE

Give an account of the Northern Plains of India class 9 social science CBSE

Change the following sentences into negative and interrogative class 10 english CBSE

Trending doubts

Onam is the main festival of which state A Karnataka class 7 social science CBSE

Fill the blanks with the suitable prepositions 1 The class 9 english CBSE

Which are the Top 10 Largest Countries of the World?

Difference between Prokaryotic cell and Eukaryotic class 11 biology CBSE

Differentiate between homogeneous and heterogeneous class 12 chemistry CBSE

The Equation xxx + 2 is Satisfied when x is Equal to Class 10 Maths

Who was the founder of muslim league A Mohmmad ali class 10 social science CBSE

Select the word that is correctly spelled a Twelveth class 10 english CBSE

Give 10 examples for herbs , shrubs , climbers , creepers