Two balls having masses m1=5 kg and m2=10 kg moving with velocities u1=10 m/s and u2=5 m/s collide elastically. Find the change in momentum of the ball having mass m1 due to collision
A
110 kgm/s
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
90 kgm/s
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
−100 kgm/s
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
50 kgm/s
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is C−100 kgm/s Let final velocity of ball having mass m1 is v1 and final velocity of ball having mass m2 is v2.
Given, m1=5kg,m2=10kg u1=10kg,u2=−5m/s
As we know, u1−u2=v2−v1 15=v2−v1 v2=15+v1(1)
By using conservation of momentum m1u1+m2u2=m1v1+m2v2 (5×10)+(5×(−10))=(5×v1)+(10×v2) 0=(5×v1)+(10×v2)
By using eq (1) in above equation we get, −(5×v1)=(10×(15+v1)) −30=3v1 v1=−10m/s
We know change in momentumΔp=mΔv=m(vf−vi)=m1(v1−u1)=5(−10−10) kgm/s=−100 kgm/s