What is the maximum velocity of object A if its weight is doubled?

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Discussion Overview

The discussion revolves around the maximum velocity of an object (specifically a vehicle) when its weight is doubled. Participants explore the relationship between mass, force, and velocity, considering factors such as drag forces and resistance. The scope includes theoretical and conceptual aspects of physics, particularly related to motion and forces.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant proposes a scenario where an object A has a maximum velocity of 50 mph and weighs 100 lbs, questioning how doubling the weight affects this maximum velocity, referencing kinetic energy.
  • Another participant argues that velocity is not determined by mass alone, stating that while more force is needed to accelerate a heavier object, the maximum velocity is limited by other factors, including the speed of light.
  • A third participant introduces the concept of drag forces, noting that a wheeled vehicle experiences both air drag and rolling resistance, which affect its top speed.
  • Further, it is mentioned that air drag increases with velocity, and a participant suggests that a quadratic dependence is a more accurate approximation for typical vehicles than an exponential increase.
  • Another participant points out that without additional details about the vehicle, it is unclear which forces are more significant, and they express uncertainty about how the vehicle's speed would change with increased weight.

Areas of Agreement / Disagreement

Participants express differing views on how mass affects maximum velocity, with some emphasizing the role of force and others focusing on drag forces. There is no consensus on the relationship between weight and maximum velocity, and the discussion remains unresolved.

Contextual Notes

Participants note limitations in their discussion, such as the need for more details about the vehicle and the specific conditions affecting its speed. The assumptions regarding drag forces and their impact on velocity are also highlighted as areas requiring further clarification.

BeefSteak
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I was thinking of an object let's say object A has a maximum velocity of 50mph and weighs 100lbs if I added another 100lbs what would be the maximum velocity of the object A? I also want to know what topic is this concern for me to study and enable myself to answer this types of question.So I was thinkg KE = 1/2(mv^2)

 
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Velocity isn't determined by mass, so the question isn't really sensible. The only limit on the velocity is the speed of light. It takes a force to increase the velocity of an object, and the faster you want to go and the heavier an object is the more force you need to get to that point. So doubling the mass would simply mean you'd need more Force to accelerate the object to get to 50 mph. This is the whole idea behind Newton's Second Law.
 
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BeefSteak said:
I was thinking of an object let's say object A has a maximum velocity of 50mph and weighs 100lbs if I added another 100lbs what would be the maximum velocity of the object A? I also want to know what topic is this concern for me to study and enable myself to answer this types of question.So I was thinkg KE = 1/2(mv^2)

Hi, BeefSteak, I hope you did not let yourself frighten away . Welcome to PF! This is a good place, if you stick to the rules. You are offered a template when you start a thread, and you must not delete it.
I wonder what your question really is. What do you mean on maximum velocity? Please, copy the whole problem text.
 
A (wheeled) vehicle has two drag forces limiting its top speed.
(level ground assumed)
1) air drag force, which increases (exponentially) with velocity.
2) rolling resistance drag force which is deemed to be constant regardless of velocity, and depends on :
mass (m) in kg
local gravity rate (g) (9.81 m/s/s is usual)
tyre to road rolling resistance co-efficient (Crr) (0.03 is a good figure)
Assuming all the tyres are the same, the rolling resistance drag force (f) in Newtons you get from :
f = m * g * Crr
 
dean barry said:
1) air drag force, which increases (exponentially) with velocity.
An exponential increase would be very unusual, for typical vehicles and the given speed a quadratic dependence is a much better approximation.

Without more details of the vehicle, we cannot tell which influence is more important, and we also don't know what limited the speed before. It is unlikely (but not impossible) that the vehicle will be able to become faster, it is unlikely that its top speed will go down below half of the original value, but everything in between is possible.
 

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