Get Answers to all your Questions

header-bg qa

A knife of mass m is dropped from height h on the ground . It penetrate the block from distance 'S '  then find out friction force acting on knife 

Option: 1

\frac{mg(h+s)}{s }


Option: 2

\frac{mgh}{(h+s)}


Option: 3

\frac{mgh}{s}


Option: 4

\frac{mgs}{h}


Answers (1)

best_answer

As we have learned

Work Energy Theorem -

Work done by all the forces acting on a particle equal to change in kinetic energy

-

 

 

Total work done by all forces  = Change in K.E 

W = W_g + W _ f = 1/2 m [ v _{f}^{2}- v_{i}^{2}]

W_g +W_f = 0

mg(h+s) - f_\sigma s = 0

f_\sigma = \frac{mg(h+s)}{s}

 

 

 

 

 

Posted by

Anam Khan

View full answer

NEET 2024 Most scoring concepts

    Just Study 32% of the NEET syllabus and Score up to 100% marks