Reference no: EM132512912
Please help me:
Ahmad is driving North on Highway 69 at 90 km/h and sees a large moose on the road. He quickly slams on his brakes, but his reaction time is 0.85 s (as he sees the moose, thinks about his response, and then presses the brake pedal). He presses the brake for 3.5 s and comes to a stop just in time.a) Find the distance travelled after seeing the moose and before pressing the brake.
b) Find the total distance he travelled before coming to a stop.
c) Find the average acceleration once he presses the brake.
2. Sanna rolls a ball up to another person on a smooth ramp 19.6 m above her. The ball reaches the other person's hands when it is travelling 4.9 m/s uphill. If the ramp angle slows the ball down by 3.7 m/s each second it travels up the ramp, find the initial velocity of the ball.
3. A car waits at a red light for a few seconds, and then accelerates straight ahead to 54 km/h in 3.1 s and then cruises at a constant speed for 75 m. The road is straight. Find the total distance and time travelled.
4. A young girl gives her toboggan a push of 4.0 m/s up a hill. It slides up the hill slowing down at an acceleration of 8.0 m/s2 [down]. It comes to a stop and then slides back towards her speeding up at the same rate as it slowed down on the way up. If the girl has to run 48 m down the hill from where it first was pushed to get to where her sled stopped, find the elapsed time for the journey.
5. A porpoise jumps straight up and crashes back into the water at 8.9 m/s. The drag and buoyancy forces of the water slow the porpoise down with an acceleration of -9.3 m/s2 as the porpoise finally slows to a stop. Find the depth the porpoise reaches.