Question

from a roof top a rifle is fired with a steady blowing wind. The time interval between the flash and the report,observe at 1km away is 5seconds.find the velocity of sound in air

Answer 1

A bullet of mass 1.0×10−3 kg embeds itself in a wooden block with mass 0.992 kg , which then compresses a spring (k = 140 N/m ) by a distance 5.0×10−2 m before coming to rest. The coefficient of kinetic friction between the block and table is 0.41.