This question is an exact duplicate of:
Which of the sp³-sp³ or sp³-sp² forms a more stronger bond.. As we know that former one will make weaker bond as both are larger orbitals but in latter one.. One is bigger and other smaller.. So latter one would be a stronger bond.. But if we see by other thing tbat similar Orbitals make more effective bond.. Then sp3-sp2 should make a weaker bond.. So which of the two would actually make up for a stronger bond?