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Question

Problem Set:Final Velocity and Displacement

1) A bike rider accelerates constatntly to a velocity of 7.5m/s during 4.5 sec. The bike's displacement is +19m. What was the initial velocity of the bike?


2)The pilot stops the same plane in 484m using a constant acceleration of 8.0m/s^2. How fast was the plane moving before braking began?


3)A person with a shoulder harness can survive a car crash if the acceleration is smaller than -300m/sec^2. Assuming constant acceleration, how far must the front end of the car collapse if it crashes at 101km/hr?


4) A car is initially sliding backwards down a hill at -25km/hr. ZThe driver changes the direction of the car. By the time the car's velocity is is + 35km/h, it is 3.2 m from its starting point. Assuming the car was uniformly accelerated, find the acceleration.



Please help me explain any answer, this will be very helpfull. Thank you:)

Answer 1

I have consulted our local wiz and ...


S=V0t + 0.5at^2
V=V0 + at

19 = V0(4.5) + 0.5 a(4.5)^2
7.5 = V0 +a (4.5)

Can you solve for V0?

2) Again

V=at
t=sqrt(2S/a)
3) Hmmm...Sounds like homework to me ....

Answer 2

i'm sorry to pay attention that Jack. i'm no wiz yet I even have some low-priced recommendations. a million. attempt blowing into the hollow. in case you generate sufficient air velocity the ball will come out. I doubt you have the lungs for it. 2. Blow perpendicular to the hollow... that could artwork too. 3. next time chew gum and enter the room on an identical time. Attache a chewing gum to a string then attache the ball to the chewing gum...Ah.. you haven't got chewing gum? 4. that's in basic terms a hollow interior the floor. basically dig it up! ______ (?) The cat has a sturdy theory. not sturdy for you, in spite of the shown fact that it truly is robust theory.... I advise she provides the ping-pong ball. effective cat! 5. Use a pointy persist with impale the ball and bring it slowly up. 6. Pst... i'm hoping no person listens.. it is style disgusting in spite of the shown fact that it may artwork Why do not you pee in that hollow... Archimedes regulation and all that...

Answer 3

3) d = 101/300 = 0.337 meter
4) a (25 + 35) / (3.2)^2 = 4.88 m/s^2