The Highway Code gives this information about the stopping distance of a car - Edexcel - GCSE Physics - Question 1 - 2012 - Paper 1
Question 1
The Highway Code gives this information about the stopping distance of a car.
speed = 30 miles per hour
thinking distance = 9 m
braking distance = 14 m
(a)
(i) Wh... show full transcript
Worked Solution & Example Answer:The Highway Code gives this information about the stopping distance of a car - Edexcel - GCSE Physics - Question 1 - 2012 - Paper 1
Step 1
What is the stopping distance?
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Answer
The stopping distance is the total distance the car travels while coming to a complete stop, which is the sum of the thinking distance and the braking distance. Given the thinking distance is 9 meters and the braking distance is 14 meters, the stopping distance can be calculated as follows:
Complete the sentence by putting a cross (✔) in the box next to your answer.
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Answer
The driver’s thinking distance is most likely to increase when A the driver is tired. This is because fatigue can impair the driver's reaction time, leading to a longer thinking distance before the brakes are applied.
Step 3
Calculate the momentum of the car.
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Answer
Momentum (p) is calculated using the formula:
p=mimesv
where:
m = mass of the car = 800 kg
v = velocity of the car = 3.0 m/s
Substituting the values:
p=800extkgimes3.0extm/s=2400extkgm/s
Thus, the momentum of the car is 2400 kg m/s.
Step 4
Calculate the work done by the braking force.
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Answer
The work done (W) by a force is given by the formula:
W=Fimesd
where:
F = force = 600 N
d = distance = 15 m
Substituting the values:
W=600extNimes15extm=9000extJ
Therefore, the work done by the braking force is 9000 J.
Step 5
Complete the sentence by putting a cross (✔) in the box next to your answer.
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Answer
The work done by the brakes during braking is equal to A the energy transferred. This is because the work done by the brakes is the energy needed to stop the car, transforming kinetic energy into heat and other forms.
