Question:Is it necessary to dust off the hands after striking them for tayammum?

Answer:In the name of Allah, it is not necessary. Allah knows best.

Question:In case of tayammum as a replacement for Janabat ghusl (ritual washing), is it permissible to pray without ablution?

Answer:In the name of Allah, if the tayammum was done instead of Janabat ghusl with the availability of the conditions, the prayer is valid without ablution, but the person remains in the state of janabat, therefore he has to perform ghusl after the need for tayammum is lifted. Allah knows best.