Question
Question: Two putty balls of equal mass moving with equal velocity in mutually perpendicular directions, stick...
Two putty balls of equal mass moving with equal velocity in mutually perpendicular directions, stick together after collision. If the balls were initially moving with a velocity of 452ms−1 each, the velocity of their combined mass after collision is
A
452ms−1
B
45ms−1
C
90ms−1
D
22.52ms−1
Answer
45ms−1
Explanation
Solution

Initial momentum P=m452i^+m452j^⇒ ∣P∣=m×90
Final momentum 2m×V
By conservation of momentum 2m×V=m×90
∴V=45 m/s