Question

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

Answer 1

Answer:

t = 0.05 sec

Explanation:

Don't forget to Mark me as brainliest

Answer 2

The time taken during the retardation is 0.05 seconds.

Explanation:

Step 1:

From the given statements, we know ,

Initial Velocity (u) = 16 m/s

Final Velocity (v) = 0 m/s

Distance travelled (s) = 0.4 m

Step 2:

To Find the time (t) taken, let us firstly find the retardation (a)

From Newton’s 3rd Equation of Motion

$v^{2} = u^{2} + 2as$

Substituting the values in the above Equation

$0 = 162 + 2\times a \times 0.4$

$a = \frac{ (-16\times 16)}{(2\times0.4)}$    

 $= -320 \frac{m}{s^{2} }$    

[-ve sign shows the retardation]

Step 3:

Now putting the value of retardation (a) in Newton’s 1st Equation of motion

 v = u + at

0 = 16 + (-320)t

$t = \frac{16}{320}$

   = 0.05 seconds

Therefore the time taken is 0.05 s