A man (mass =50kg ) and his son (mass =20kg ) are standing on a frictionless surface facing each other. The man pushes his son so that he starts moving at a speed of 0.70ms−1 with respect to the man. The speed of the man with respect to the surface is:
Held on 12 Apr 2019 · Verified 6 Jul 2026.
0.20ms−1
0.14ms−1
0.47ms−1
0.28ms−1
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