Question

10grams of bullet is fired from a rifile horizontally 5kg block of wood suspended by string and the bullet get embed in wood height is 2.5cm the velocity of bullet

Answer 1

$\underline{ \boxed{ \mathfrak{ \orange{ \huge{Answer}}}}} \\ \\ \star \: \boxed{ \mathfrak{ \red{Given}}}$

Mass of bullet (m) = 10 g = 0.01 kg

Mass of block (M) = 5 kg

Height (h) = 2.5 cm = 0.025 m

initial velocity of bullet = V

final velocity of combination = 0

$\star \: \boxed{ \mathfrak{ \blue{To \: Find}}}$

intial velocity of bullet....

$\star \: \boxed{ \red{ \mathfrak{Concept \: and \: Formula}}}$

In this question total energy of system is conserved so as per energy conservation law...

$\: \: \: \: \: \: \: \: \: \: \: \: \underline{ \boxed{ \mathfrak{ \pink{ \frac{1}{2} M {V}^{2} = mgh}}}}$

$\star \: \boxed{ \mathfrak{ \blue{Calculation}}}$

$\mapsto \rm \: \frac{1}{2} \times 0.01 \times {V}^{2} = 5 \times 10 \times 0.025 \\ \\ \mapsto \rm \: {V}^{2} = \frac{5 \times 10 \times 0.025 \times 2}{0.01} = 250 \\ \\ \underline{ \boxed{ \orange{ \mathfrak{V = 15.81 \: \frac{m}{s} }}}}$