Question

20 N 30 N 3. (a) "U" 10 m2 Vom SKIN SKIN Calculate the pressure with which two iron nails are penetrating in the skin. Calculate the pressure exerted by ball falling on earth. (b) m = 50 g r Spherical ball having radius = 5 cm​

Answer 1

Explanation:

Given, mass of the bullet, m=20g=0.02kg ;

initial velocity of the bullet, u=500m/s ;

final velocity of the bullet, v=400m/s

Work done by the tree against the bullet,

W

tree

=

2

1

mv

2

−

2

1

mv

2

=

2

1

m(v

2

−u

2

)

=

2

1

(0.02)[(400)

2

−(500)

2

]=−900J

Work done by the bullet, W

bullet

=−W

tree

or W

bullet

=−(−900J)=900J