5. a 5 mhz ultrasonic transducer is used for measuring blood flow in a vessel of 6 mm internal diameter. if the average doppler frequency is 4000 hz and doppler angle is 60o, what is the average flow rate? assume the flow velocities are constant in the vessel and the sound speed in blood is 1540 m/sec.

Consider a large isothermal enclosure that is maintained at a uniform temperature of 2000 k. calculate the emissive power of the radiation that emerges from a small aperture on the enclosure surface. what is the wavelength ? , below which 10% of the emission is concentrated? what is the wavelength ? 2 above which 10% of the emission is concentrated? determine the wavelength at which maximum spectral emissive power occurs. what is the irradiation incident on a small object placed inside the enclosure?