Prelim Physics help!! (1 Viewer)

[lookoutastroboy]

Hey guys,

I've got these 2 physics questions that I cannot do - if you know how to solve them, could you please post your full solution if possible =) Here goes -

1. A car 4.0 m long came up behind a semi-trailer 20.0m long travelling at a steady 72km/hr. After travelling behind the semi-trailer for some time, the driver of the car decided to overtake. If the car pulled out from behind the semi-trailer with the front of the car 10.0 m behind the rear of the trailer and accelerated at 3.5 ms^-2 until the rear of the car was 10.0 m in front of the truck, how far would the car travel and how long would it take?

2. A plane is flying parallel to the ground, with a velocity of 750 km h^-1, and at an altitude of 4.90 km. A lump of lead is dropped from the plane. How long before the lead reaches the ground (slightly easier, i think)



Thanks in advance and good luck,
lookoutastroboy

 

[ilikebeeef]

Re: Physics help!!

Use your formulas

v=u+at
s=ut + (1/2)at^2
v^2=u^2+2as

Just a hint there.