A bullet of mass 10 g moving with a speed of 20 m / s hits an ice block of mass 990 g kept on a frictionless floor and gets stuck in it How much ice will melt if 50 % of the lost KE goes to ice? (initial temperature of the ice block and bullet =0° C )

Question

A bullet of mass 10 g moving with a speed of 20 m / s hits an ice block of mass 990 g kept on a frictionless floor and gets stuck in it How much ice will melt if 50 % of the lost KE goes to ice? (initial temperature of the ice block and bullet =0° C ) (A) 0.001 g (B) 0.002 g (C) 0.003 g (D) 0.004 g

Tardigrade Admin · Accepted Answer

50 % of lost KE goes to melt ice ⇒ (1/2) × (1/2) × (10 × 20 × 20/1000)=1 J Amount of ice that melts =(1/80 × 4.2)=0.003 g

Q. A bullet of mass $10 g$ moving with a speed of $20 m / s$ hits an ice block of mass $990 g$ kept on a frictionless floor and gets stuck in it How much ice will melt if $50%$ of the lost KE goes to ice? (initial temperature of the ice block and bullet $= 0^{\circ} C$ )

0.001 g

0.002 g

0.003 g

0.004 g

$50%$ of lost KE goes to melt ice
$\Rightarrow \frac{1}{2} \times \frac{1}{2} \times \frac{10 \times 20 \times 20}{1000} = 1 J$
Amount of ice that melts $= \frac{1}{80 \times 4.2} = 0.003 g$

Q. A bullet of mass 10g moving with a speed of 20m/s hits an ice block of mass 990g kept on a frictionless floor and gets stuck in it How much ice will melt if 50% of the lost KE goes to ice? (initial temperature of the ice block and bullet =0∘C )