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I Need Some Help With Physics!!!!!!!!!! (1 Viewer)

asj1031

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If you could do them, please explain me the working outs.!!!!

thanks very muchh


Q1 In acapulo, on the coast of mexico, professional high divers plunge from a height of 36m above the water. (the Highest diving boards in Olympic diving events are 10m above the water.) Estimate:
a) the length of the time interval during which the divers fall thorugh the air

b) the speed with which the divers enter the water.

Assume that through out their dive, the divers are falling vertically from rest with an acceleration of 9.8m/s^2.


Q2. A brand new Rolls- Royce rolls off the back of a truck as it is being delivered to its owner. It lands on its wheels. The truck is travelling along a straight road at a aconstant speed of 72 km/h (20 m/s). The Rolls-Royce slows down at a constant rate, coming to a stop over a distance of 240m. It is a full minute before the truck driver realises that the precious load is missing. The driver brakes immdediately, leaving a 25m long skid mark on the road. The driver's reaction time (time interval between noticing the problem and depressing the brake) is 0.5s. how far back is the Rolls-Royce when the truck stops?
 

z600

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1)a)
Change in time squared =2 times change in displacement all over acceleration
dt^2=2 x 36 /9.8
time = 7.35 seconds

1)b)
V^2= initial v + 2 x acceleration x displacemnt
v^2= 0 + 2 x 9.8 x 36
v=26.56m/s

the second one should be 1475m (too lazy to do working)
*edit, i saw u want the working so here it is

in the 1 minute the travelled without the rolls royce the truck went 1.2 KM
The reaction time cause the truck to go a further 10m
The skid mark was 25m
and the rolls royce rolled off and travelled 240
add them up you get 1475!
 
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