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Why if the speed of a car is doubled its braking distance is much more than doubled?
Wiki User
∙ 12y ago
Because kinetic energy KE ~ V^2 (varies as the square of the speed). So ke ~ v^2 and KE ~ V^2 and when V = 2v, doubled, we have KE/ke = (V/v)^2 = (2v/v)%2 = 4 so that KE = 4 ke. QED. The new kinetic energy is four times the old.
And, ta da, that means there is four times as much energy for the brakes to sap and reduce to zero kinetic energy, which means V = 0 is the end speed (stopped). So by the work function, which you should know by now, we have WE = FS where F is the braking force (friction) and S is the stopping distance. We assume the braking force remains the same for both speeds.
Then KE - WE = 0, meaning the kinetic energy is sapped by the work so there is none left. And we have KE = WE = FS; so S = WE/F = KE/F and the stopping distance varies as the kinetic energy. So when the speed is doubled and the kinetic energy is quadrupled, the stopping distance is quadrupled because there is now four times as much kinetic energy to expend in stopping. QED.
Wiki User
∙ 12y ago
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How many times more distance does it take to stop when speed is doubled?
Assuming a constant, linear deceleration, it takes four times the distance to stop when you double your speed. Using the formula v2 = u2 + 2as where v is final speed u is initial speed a is acceleration s is distance We can rearrange the formula to solve for s giving: s = (v2 - u2)/2a If we are finding the distance to that it takes to stop, the final velocity will be 0. Therefore distance to stop is given by s = -u2/2a Now we will look at the distance it takes to stop when speed is doubled. This will make our initial speed 2u. s = -(2u)2/2a = -2u2/a Comparing the two, we can see that when initial speed is doubled, it takes four times the distance to stop. (While it may look strange in the formula to have a negative sign in a distance measurement, remember that the car is decelerating, giving a negative acceleration. This means that the overall expression for distance will be positive.)
What is more faster km or hr?
Neither. These units measure distance and time, not speed.
What is an equation that relates two or more quantities?
A mathematical formula, such as Speed = Distance / Time for example.
What is the Average speed of 97.7 km?
97.7 kilometres (km) is a measure of distance. It makes no sense to try to convert that into a measure of speed: the distance could be traversed by electromagnetic radiation (light, for example) in less than a third of a millisecond, or more than a year for a slow snail.
What is formula of speed?
The definition of speed: speed = distance / time. You can also write this as distance = speed x time. This is used to do various calculations related to speed. The above is actually only valid for a constant speed. If the speed changes over time, speed - or more precisely velocity - is defined (using derivatives) as v = ds/dt. However, you need to have basic notions of calculus to work with this.
Double your speed double stopping distance?
If you double your speed, your stopping distance will quadruple due to the relationship between speed and stopping distance. It's important to remember that increasing speed significantly impacts the time it takes to bring a vehicle to a complete stop.
How does speed traction and gravity affect braking distance?
Speed: As speed increases, braking distance increases because the vehicle has more kinetic energy that needs to be dissipated in order to come to a stop. Traction: Higher traction allows the tires to grip the road better, reducing braking distance. Lower traction conditions, such as wet or icy roads, can increase braking distance due to reduced grip. Gravity: Gravity affects braking distance by influencing the weight and load distribution of the vehicle. Heavier vehicles may have longer braking distances as it takes more force to slow them down compared to lighter vehicles.
Braking distance changes with the weather?
in rain, snow or ice your tires have much less traction, and therefore need more braking distance.
Does your stopping distance increase or decrease with speed?
Stopping distance generally increases with speed. This is because as your speed increases, it takes longer to react to a hazard and the vehicle covers a greater distance while stopping. Additionally, higher speeds require more braking force to bring the vehicle to a complete stop.
How does mass affect braking distance?
Mass directly affects braking distance because a heavier vehicle has more momentum and kinetic energy, requiring more force to bring it to a stop. More mass results in a longer braking distance as it takes more time for the vehicle to slow down and stop. Additionally, heavier vehicles may have larger braking distances due to increased friction and heat generated during braking.
How many times more distance does it take to stop when speed is doubled?
Assuming a constant, linear deceleration, it takes four times the distance to stop when you double your speed. Using the formula v2 = u2 + 2as where v is final speed u is initial speed a is acceleration s is distance We can rearrange the formula to solve for s giving: s = (v2 - u2)/2a If we are finding the distance to that it takes to stop, the final velocity will be 0. Therefore distance to stop is given by s = -u2/2a Now we will look at the distance it takes to stop when speed is doubled. This will make our initial speed 2u. s = -(2u)2/2a = -2u2/a Comparing the two, we can see that when initial speed is doubled, it takes four times the distance to stop. (While it may look strange in the formula to have a negative sign in a distance measurement, remember that the car is decelerating, giving a negative acceleration. This means that the overall expression for distance will be positive.)
What happens to the stopping distance when the vehicle speed increases?
The distance needed to stop also increases.
Does speeding have an effect on braking distance?
Yes, the faster you are moving the longer it will take to stop.
Does high speed increase stopping distance greatly?
Yes, high speed greatly increases stopping distance because the faster a vehicle is traveling, the longer it will take to come to a complete stop. At higher speeds, the vehicle has more kinetic energy that needs to be dissipated through braking, resulting in a longer stopping distance.
When training to drive a truck, do you have to do high speed braking from 100 mph or more?
Most trucking companies do not require you to do high speed braking for speeds of the extent. Normally when you are driving a truck, your speed shouldn't exceed 70 MPH due to speed limits. They will teach you high speed braking though to prepare you for a worse case scenario.
Speeding has no effect on braking distance?
Speeding does affect braking distance. The faster a vehicle is traveling, the longer it will take to come to a complete stop because there is more kinetic energy that needs to be dissipated through braking. This means that speeding can increase the risk of accidents due to longer braking distances.
What road surface has longest braking distance?
A road surface with loose gravel or sand tends to have the longest braking distance due to the reduced tire traction. When braking on loose surfaces, vehicles are more likely to skid before coming to a complete stop, increasing the distance required to brake.
