7. The diagram shows information about the first 8 seconds of a car journey. Speed (m/s) 0 6 Time (seconds) له NOT TO SCALE The car travels with constant acceleration reaching a speed of vm/s after 6 seconds. The car then travels at a constant speed of vm/s for a further 2 seconds. The car travels a total distance of 150 metres. Work out the value of v. DISTANCE = AREA UNDER CURVE D' = A + A D= ± 6h + wil 150 150 ½ (6-0) (v) + (8-6)(v) =(6-0)(v) 1.6. v + 24 1/2 30 150 3V+24 150 = 54 130 7/22 v= 30

9

During each cycle, the velocity (v in mm/s) of a piston is v=18t−18t^2, where t is the time in seconds. Find the displacement "s" of the piston after 0.25 seconds if the initial displacement is zero.   Round to 3 decimal places.  ____________mm

Assume that the rate of change of air pressure with altitude (distance above the earth) is proportional to the air pressure. If the air pressure on the ground is 14.7 psi and if at an altitude of 10, 000 ft it is 10 psi, find the air pressure at an altitude, and find the air pressure at an altitude of 15, 000 ft.Ans. 8.372 psi

8. A dog chases a squirrel at a rate of 3 m/s. The squirrel dashes up a tree trunk (vertical) at the rate of 2 m/s. Find the rate of change of distance between the squirrel and the dog at the instant when the dog is 12 m from the tree trunk and the squirrel is 5 m up the trunk.

How can I find the average rate of change?

A winch at the top of a 12-meter building pulls a pipe of the same length to a vertical position, as shown in the figure. The winch pulls in rope at a rate of -0.4 meter per second ds --0.4 m/sec). Find the rate of horizontal change (in m/sec) and the rate of vertical change (in m/sec) at the end of the pipe when y3. (Round your answer to three decimal places.) horizontal vertical Anon m/sec m/sec

A car's position in feet t seconds after it starts moving is given by s(t)-9t/t. The average rate of change in position with respect to time is called average velocity %3D ) Find the car's average velocity over the first 4 seconds. DO NOT INCLUDE UNITS WITH YOUR ANSWER. i) Find the car's average velocity from t = 16 to t = 25 seconds. DO NOT INCLUDE UNITS WITH YOU ANSWER. i) What units would your answers from parts i and ii be in? O A. feet O B. feet per second OC. seconds O D. seconds per foot per foot O E. feet per second per second OF. seconds per foot