Question

A buttet of 10g strike a sand bag at a speed of 1000m/s and get embedded after travelling 5cm.what is the resistive force exerted by sand on bullet

Answer 1

Answer:

-100000 N

Explanation:

mass of the bullet [m] = 10g = 10/1000 kg

initial velocity [u] = 1000m/sec

final velocity [v] = 0m/sec    [ bullet came to rest]

displacement [s] = 5cm = 5/100 m

so acceleration = by third equation of motion

2as  = v² -u²

2a × 5/100 = 0² - 1000²                                               [ 5/100 = 1/20]

2a × 1/20  = -1000000

2a          =  -1000000×20 = -20000000

a = -20000000/2 = -10000000 m/sec²

now,

force = mass × acceleration

           10/1000 ×-10000000   = -100000 N   [ (-) show force act in opposite direction]

hope it helps you very well