Musschenbroek came from a family of instrument makers in Leiden in the Netherlands. He studied at the University of Leiden, where he gained an MD in 1715 and a PhD in 1719. After holding a chair of medicine at Duisburg (1721–23) and of natural philosophy at Utrecht (1723–40), Musschenbroek returned to Leiden and served as professor of physics until his death.

On 20 April 1746 Musschenbroek reported in a letter to René Reaumur details of a new but dangerous experiment he had carried out. He had suspended, by silk threads, a gun barrel, which received static electricity from a glass globe rapidly turned on its axis and rubbed with the hands. From the other end he suspended a brass wire, which hung into a round glass bottle, partly filled with water. He was in fact trying to ‘preserve’ electricity by storing it in a nonconductor.

When Musschenbroek held the bottle with one hand while trying to draw sparks from the gun-barrel he received a violent electric shock. He had accidentally made the important discovery of the Leyden jar – an early form of electrical capacitor. It was an event that captured both the popular and the scientific imagination and led to much effort by such scientists of the latter half of the 18th century as Benjamin Franklin to understand the nature and behavior of electricity. The German inventor Georg von Kleist independently discovered the Leyden jar in 1745.