Can rapid acceleration have momentum?

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A top fuel dragster can accelerate from 0 to 300 mph in just 4 seconds. In the first scenario, when the dragster is traveling at a constant speed of 300 mph and the driver cuts the fuel delivery, the speed will immediately decrease due to the loss of force from the engine. In the second scenario, even though the dragster is accelerating and reaches 100 mph in 1 second, cutting the fuel delivery will also lead to a decrease in speed. The physics remains consistent: momentum, defined as velocity times mass, is maintained only when no external forces act on the object. In both scenarios, the dragster will slow down once the engine stops delivering force, as friction forces will eventually overpower the remaining momentum.
BillyJohnson1992
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A top fuel dragster can accelerate from 0 to 300mph in 4 seconds.

Scenario 1: Top fuel dragster is driving at a constant speed of 300mph. Driver cuts the fuel delivery to the engine. The speed will immediately decrease.

Scenario 2: Top fuel dragster is accelerating violently, at the 1 second mark the speed is already 100mph and going up at a dramatic pace. Driver cuts the fuel delivery to the engine. Will the speed immediately decrease?

Help! :confused:
 
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Yes, it will slow down at the moment the engine does not deliver force on the wheels anymore, and if it gets no fuel the engine cannot exert any force.

Momentum is velocity times mass. An object will keep the same momentum as long as no force is acting on it. There are different kinds of friction forces acting on the dragster and when it is speeding up (and its momentum is increasing) the force between the wheels and the ground is larger than the friction forces (air friction, friction in parts of engine and bearings). Those friction forces will slow the dragster down when there is no forward force.
 
Scenario 1: Top fuel dragster is driving at a constant speed of 300mph. Driver cuts the fuel delivery to the engine. The speed will immediately decrease.

Scenario 2: Top fuel dragster is accelerating violently, at the 1 second mark the speed is already 100mph and going up at a dramatic pace. Driver cuts the fuel delivery to the engine. Will the speed immediately decrease?

The fact that the dragster in Scenario 2 had a period of acceleration before it's period of deceleration doesn't change the physics of the situation. The velocities decrease at the same rate if all other factors are held constant.
 
An object will keep the same momentum as long as no force is acting on it.

... as long as no net external force is acting on it.
 

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