Question

A bullet traveling with a velocity of 16 m/s penetrates a tree trunk and comes to rest in 0.4m. Find the time taken during the rretardation

pls answer quickly with step by step explaination

Answer 1

Answer:

u=16 m/s (initial), v=0,s=0.4 m

Deceleration a=

2s

v

2

−u

2

=−320 m/s

2

Time =t=

a

v−u

=

−320

0−16

=0.05 sec.

please Mark as Brainlist...

Answer 2

$\dag\:\underline{\sf AnsWer :}$

In this question we are provided that, a bullet traveling with a Initial velocity (u) of 16 m/s and penetrates a tree trunk and comes to rest i.e final velocity (v) = 0 m/s and distance (s) is 0.4 m. We are asked to find the time taken during the retardation.

• First of all we need to find the retardation (a) of the bullet by using third kinematical equation of motion :

$:\implies \sf v^2 - u^2 = 2as$

$:\implies \sf (0)^2 - (16)^2 = 2a(0.4)$

$:\implies \sf - 256 = 0.8a$

$:\implies \sf a = \dfrac{ - 256}{0.8}$

$:\implies \underline{ \boxed{\sf a = - 320 \: m/s^2 }}$

• Here we have find the retardation of the bullet. So, now we can find the time taken during the retardation by using first kinematical equation of motion :

$\dashrightarrow\:\:\sf v = u + at$

$\dashrightarrow\:\:\sf 0 = 16 - 320t$

$\dashrightarrow\:\:\sf 320t = 16$

$\dashrightarrow\:\:\sf t = \dfrac{16}{320}$

$\dashrightarrow\:\: \underline{ \boxed{\sf t = 0.05 \: second}}$