Using second law of motion, derive the relation between force and acceleration. A bullet of 10 g strikes a sand-bag at a speed of 103 m s-1 and gets embedded after travelling 5 cm. Calculate (i) the resistive force exerted by the sand on the bullet (ii) the time taken by the bullet to come to rest.
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
- m =10 g
= 10 kg u
1000
=103 m/s
v = 0
s= 5 m
100
v2-u2= 2as
0-(103)2= 2a 5
100
a=−1000𝑥1000x10
2.5
=107ms-2
F= ma
=105N
- v=u+at 0=103-107t
107t= 103 t=103/107
= 10-4s
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