Answer: The correct option is (c.).
Explanation:
Mass of the cart A= 1.5 kg
Velocity of Cart A = 1.4 m/s towards right
Mass of the cart B = 1.0 kg
Velocity of Cart B = 1.4 m/s towards left
Momentum (P)= Mass × Velocity
[tex]P_A=1.5 kg\times 1.4 m/s=2.1 kg m/s[/tex]
[tex]P_B=1.0 kg\times (-1.4m/s)=-1.4 kg m/s[/tex]
(Negative sign means velocity of the cart is in opposite direction of that of the cart A)
Total Momentum =[tex]P_A+P_B=2.10 kg m/s-1.40 kg m/s=0.70 kg m/s[/tex]
Hence, the correct option is (c.).