# A brand new Rolls-Royce rolls off the back of a truck as it is beling delivered to tis owner. Full question in details?

## 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 traveling along a straight road at a constant speed of 72km/h (20m/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 realizes that the precious load is missing. The driver brakes immediately 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?

Apr 11, 2017

$995 m$

#### Explanation:

Distance traveled by Rolls-Royce after falling off the truck$= 240 m$

Distance traveled by truck in one minute after realization by driver$= \text{speed"xx"time}$
$= 20 \times 60 = 1200 m$
Distance traveled by truck during reaction time of driver $= \text{speed"xx"time}$
$= 20 \times 0.5 = 10 m$
Distance traveled by truck during making of skid mark$= 25 m$

Total distance traveled by truck after realization by driver to final halt$= 1200 + 10 + 25 = 1235 m$

Location of Rolls-Royce behind truck when the truck stops$= \text{Distance traveled by truck after Rolls-Royce fell off"-"distance traveled by Rolls-Royce after falling off}$
$= 1235 - 240 = 995 m$