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

You car is moving along in cruise control at a constant speed of 88.3 ft/s (about 60 mi/hr).  A text message appears on your phone and you look down to read it.  When you look back up at the road, you see a car at a complete stop in your lane 156 ft ahead of you.  It takes 0.39 s for you to react and apply the brakes.  When the brakes are applied your car experiences an acceleration of -32.3 ft/s2.  Fortunately, you are able to avoid hitting the other car.  What is the distance between the two cars when you come to a complete stop? (0.9 ft).

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

A snow ball, in the shape of a sphere, is melting so that its surface area is decreasing at a rate of 7 [cm? /min]. Calculate the rate its diameter is changing when its diameter measures 8 cm. Provide the full working solution for full marks. Equations you may find useful: 4 Volume of sphere 3 Surface area of sphere 4 Tr? Answer: