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the car's motion can be divided into three different stages: its motion before the driver realizes he's late, its motion after the driver hits the gas (but before he sees the police car), and its motion after the driver sees the police car. which of the following simplifying assumptions is it reasonable to make in this problem?
a. during each of the three different stages of its motion, the car is moving with constant acceleration.
b. during each of the three different stages of its motion, the car is moving with constant velocity.
c. the highway is straight (i. e., there are no curves). d. the highway is level (i. e., there are no hills or valleys).

Option (a)

Explanation:

We will discard options that don't fit the situation:

Option b: Incorrect since if the driver "hits the gas" then velocity is augmenting and it's not constant.

Option c and d: Incorrect since the situation doesn't give us any information that could be related directly to the terrain or movement direction.

Option a: Correct. At stage 1 we can assume the driver was going at constant speed which means acceleration is constantly zero. At stage 2 we can assume the driver augmented speed linearly, this is, with constant positive acceleration. At stage 3 we can assume the driver slowed the speed linearly, with constant negative acceleration.

i don't know that i agree with that but what's the question ?