a car of mass 1600 kg collides head on with a parked truck of mass 2000 kg. Spring mounted bumbers ensure that the collision is essentially elastic. If the velocity if the truck is 17 kg/h after the collision and the cars final velocity was -2.25 kg/h. What was the initial speed of the car? (m1v1,i + m2v2,i = m1v1,f + m2v2,f)

Scientists use laser range-finding to measure the distance to the moon with great accuracy. a brief laser pulse is fired at the moon, then the time interval is measured until the "echo" is seen by a telescope. a laser beam spreads out as it travels because it diffracts through a circular exit as it leaves the laser. in order for the reflected light to be bright enough to detect, the laser spot on the moon must be no more than 1.0 km in diameter. staying within this diameter is accomplished by using a special large-diameter laser. part a if λ = 540nm , what is the minimum diameter of the circular opening from which the laser beam emerges? the earth-moon distance is 384,000 km. express your answer to two significant figures and include the appropriate units.

Which of the following is not a part of the respiratory system? a. pharynx b. trachea c. pancreas d. larynx hurrim timed

Blood pressure the total amount of blood the heart pumps in one minute 2. cardiac output the number of times your heart beats in a minute 3. dilate the amount of blood that the heart can pump in a single beat 4. heart rate the force exerted on the walls of the blood vessels by the blood that moves through them 5. stroke volume to widen or get larger in size