A student claps once when standing 100 m away from a large wall. The speed of sound in air is 330 m/s.

How long after clapping does the student hear an echo?

Ascientific blank must be testable and capable of being proven false?

Which is an advantage of subdividing science into different areas?

Asquare isothermal chip is of width w=5 mm on a side and is mounted in a substrate such that its side and back surfaces are well insulated; the front surface is exposed to the flow of a coolant at tinf=15 °c. from reliability considerations, the chip temperature must not exceed t=85 °c. if the coolant is air and the corresponding convection coefficient is h=200 w/m2 x k, what is the maximum allowable "power" of the chip? if the coolant is a liquid for which h=3000 w/m2 x k, what is the maximum allowable power of the chip?