Electromagnetisim

A magnetic pulse releases from your palm, ripping the area apart and disabling the use of certain items. As soon as the spell releases (on your will for up to three rounds after the spell is first activated, in which the spell releases on its own), the following effects trigger:

• In a 45ft radius, an Electromagnetic Pulse forms in the area and instantly shocks the area, dealing 6d12 Thunder Damage to anyone inside. Any electronics inside are immediately shattered, and any flammable objects are instantly ignited, even when stored in a backpack. 
• The pulse creates a powerful force. All living creatures size Large or smaller must make a DC15 Constitution Check or be knocked prone.

On Higher Levels. 

When casting this spell using a 7'th Level Spell Slot or higher, the casting time decreases:

• Using a 7'th Level Spell Slot decreases the casting time from one minute to one round.
• Using an 8'th Level Spell Slot decreases the casting time from one minute to one action.
• Using a 9'th Level Spell Slot decreases the casting time from one minute to a bonus action.

Cancelling the Spell.

If the spell has not been released yet, you can cancel the effects of it using your action.