Question: why chcl3 has dipole moment?
Answer: Again, in case of CHCl3, the three C-Cl bonds point to one side, so a moment equal to C-Cl bond is generated as a result. ... so the resultant is greater than on C-Cl bond. This explains CH2Cl2>CCl4. In case of CH3Cl, the dipole moment of one C-Cl bond is added with moment of one C-H bond (resultant of three C-H bonds).