Question

A stone after falling for 5s from rest breakers a glass plate and in breaking so it loses 80% of its velocity . How far will it fall in the next second? (g=9.8 m/s^{2}

Answer 1

Answer:

$\boxed{\mathfrak{Displacement \ in \ 5 \ seconds = 125 \ m}} </p><p>Displacement in 5 seconds=125 m$

Given:

Initial velocity (u) = 0 m/s (Falls freely from rest)

Acceleration (a) = 10 m/s²

Time (t) = 5s

To Find:

Displacement (s) in 5 seconds

Explanation:

$\begin{gathered}\sf From \: 2^{nd} \: equation \: of \: motion : \\ \boxed{ \bold{s = ut + \frac{1}{2} a {t}^{2} }}\end{gathered}$

From2

nd

equation of motion:s=ut+ 21at 2

By substituting value of u, t & a in the equation we get:

$\begin{gathered}\sf \implies s = 0 \times 5 + \frac{1}{2} \times 10 \times {5}^{2} \\ \\ \sf \implies s = 0 + 5 \times {5}^{5} \\ \\ \sf \implies s = 5 \times 25 \\ \\ \sf \implies s = 125 \: m\end{gathered}$

⟹s=0×5+

2

1

×10×5

2

⟹s=0+5×5

5

⟹s=5×25

⟹s=125m

$\therefore$∴

Displacement (s) in 5 seconds = 125 m...