Physicists have discovered that the screeching sound of peeling Scotch tape is caused by supersonic shock waves generated within the adhesive layer [1].

This finding reveals that a common household sound is actually the result of high-speed physics typically associated with jet aircraft. By identifying the mechanism behind the noise, researchers can better understand how materials fracture under stress at extreme speeds.

The study was led by Dr. Michael K. Kelley of the University of California, Berkeley, and his collaborators [1]. To observe the phenomenon, the team used Scotch tape adhered to a glass plate that was two centimeters thick [1]. They captured the process using a high-speed camera recording at 2 million frames per second [2].

The researchers found that as the tape is peeled, cracks propagate through the adhesive layer [3]. These cracks travel faster than the speed of sound within that specific material, meaning they are supersonic [3]. This movement creates a shock wave that radiates outward as an audible squeal [1].

"The cracks travel at supersonic speeds, generating a shock wave that we hear as a squeal," Kelley said [1].

The team noted that this process is a scaled-down version of larger atmospheric events. "It’s the same physics as a sonic boom, just on a much smaller scale," the lead author of the study said [2].

This research, published in February 2026, provides a precise explanation for a sound that had previously been poorly understood [1]. The use of ultra-high-speed imaging allowed the team to visualize the crack front as it broke the sound barrier within the adhesive [2].

“"The cracks travel at supersonic speeds, generating a shock wave that we hear as a squeal,"”

This discovery demonstrates that supersonic phenomena are not limited to aerospace engineering but occur in everyday materials. By proving that adhesive failure can trigger shock waves, the research provides a framework for studying rapid material degradation and acoustic emissions in industrial polymers.