Question

lf the two bodies moving at right angles collide and their initial momenta are ${\overrightarrow{P}}_1$ and ${\overrightarrow{P}}_2$, their resultant momentum after collison is :

• A. $\overrightarrow{P_1}-{\overrightarrow{P}}_2$
• B. ${\overrightarrow{P}}_1\sim {\overrightarrow{P}}_2$
• C. $\sqrt{{\overrightarrow{P_1}}^2+{\overrightarrow{P}}_2^2}$
• D. $\sqrt{{\overrightarrow{P_1}}^2-{\overrightarrow{P}}_2^2}$

Answer 1

Answer: (C)

$\sqrt{{\overrightarrow{P_1}}^2+{\overrightarrow{P}}_2^2}$

By momentum conservation,
Resultant momentum after collision = Resultant momentum before collision = $\sqrt{{\overrightarrow{P_1}}^2+{\overrightarrow{P_2}}^2}$