Penny SPI QUESTIONS WITH COMPLETE SOLUTIONS

Which of the following is used to eliminate the low-frequency signals that appear as noise as a result of wall/valve motion? A. High-pass filter B. Bass-thump filter C. Low-pass filter D. High-frequency filter CORRECT ANSWERS: A. High-pass filter AKA wall filter AKA wall-thump filter According to Poiseuille, the most significant contributor to flow is: A. Length of vessel B. Viscosity C. Radius D. Pressure CORRECT ANSWERS: C. Radius *Poiseuille's Law Volume flow rate = π(pressure difference)(radius)^4 / 8(viscosity)(length) Sound travels for 26µs in soft tissue and encounters a reflector. how far away is the reflector? CORRECT ANSWERS: 4cm *It takes 6.5µs to propagate 1cm 26/6.5=4 contrast harmonics CORRECT ANSWERS: - As an ultrasound pulse interacts with micro bubbles, a small amount of energy is converted from the fundamental frequency to the harmonic frequency. - harmonics = nonlinear pattern The depth at which sound has lost half or 3dB of its intensity is called (x3) CORRECT ANSWERS: - Half-value layer thickness - Half-intensity depth - Partial volume layer thickness If the gain of an amplifier is 18 dB, what will the new gain setting be if the gain setting is reduced by one-half? CORRECT ANSWERS: 15 dB *3dB makes 1/2 gain reduce _________ is used for processing the signal of a bidirectional Doppler. CORRECT ANSWERS: Phase quadrature *This is used to detect positive and negative frequency shifts Which of the following is the highest of all of the time intensit