2. a Snow Avalanche Moving with a Velocity of 8.0 M/S Undergoes an Acceleration of 1.5

SPH3U The Big 5 Kinematic Equations

1. The Porsche 917/30 Can-Am car (the fastest production model built as of January 1987) can accelerate from zero to 320 km/h [forward] in 12.6 s and has a recorded top speed of 411 km/h. What is its acceleration in m/s2? 2. A snow avalanche moving with a velocity of 8.0 m/s undergoes an acceleration of 1.5 m/s2 for 6.0 s. What is the final velocity of the avalanche? 3. Jennifer is driving her Honda Civic above the speed limit on a straight level highway when she receives a warning that a police car is ahead. She decelerates at 5.0 (km/h)/s for 6.0 s to reach a velocity of 100 km/h. How fast is Jennifer going when she receives the warning? 4. Henry drives his tank initially at 14 m/s in a 50 km/h zone. He accelerates at 2.0 m/s2 to a final velocity of 28 m/s. How long does it take the tank to reach the final velocity? 5. The burning of the second engine of a two-stage toy rocket accelerates the rocket from 60 km/h [up] to 145 km/h [up] in 5.0 s. Calculate the average acceleration of the rocket in (km/h)/s. 6. In the 74 s after lift-off, the shuttle Challenger travels 36 km. Assuming constant acceleration, calculate a) the acceleration of the shuttle in m/s2. b) the speed of the shuttle in km/h after 74 s. 7. Bill takes his brother’s car out for a joy ride and steps on the gas; the car accelerates at 0.8 m/s 2 from a rest position. How far away is he when his brother notices the car gone 30s later? 8. Bill borrows his Dad’s plane and starts down the runway at 2 m/s accelerating at 1.5 m/s2. He accelerates for 1 min before the plane takes off. Can Bill take off if the runway is only 2500 m or does he crash? 9. Later that day when Bill returns his brother’s car, he drives up the driveway at 12 m/s and slams on the brakes, decelerating at 1.2 m/s2. If the garage is 59 m away, does he hit or stop in time?

Answers: 1) 7.05 m/s2, 2) 17 m/s, 3) 130 km/h, 4) 7 s, 5) 17 km/h/s, 6) a) 13 m/s2, b) 3.5 x 103 km/h, 7) 360 m, 8) he crashes (he requires 2820 m), 9) he hits (he requires 60 m to stop) Problems Free Fall

For each question draw a diagram and sign convention.

1 Bill borrows his Dad’s gun and when he gets outside he fires it straight up into the air. If the bullet left the gun at 400 m/s a) How far had it moved up after 4 s? b) How fast was it going at this time?

2 How long does it take for the bullet in question 1 to reach its highest point?

3 Bill fires a rocket up from the ground at 200 m/s. a) How long does it take to reach its maximum height? b) How high does it go?

4 To get rid of the gun, Bill throws it off a cliff at 3 m/s down. He hears the gun hit the ground 8 s later. a) What speed was it going when it hit the ground? b) How far down is the bottom of the cliff?

Answers: 1. a) 1522 m [up], b) 361 m/s [up] 2. 41 s, 3. a) 20 s, b) 2041 m [up], 4. a) 81 m/s [down], b) 338 m [down]