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A 735 kg car moving at 20 ms brakes to a stop The brakes contain about 15 kg of iron which absorbs the energy What is the increase in temperature of the brakes?
Wiki User
∙ 14y ago
kinetic energy = 0.5 x 735 x 202 = 147kJ
irons heat capacity is 0.45 J/g K
147,000/ 0.45 x 15,000 = 21.7777o
Wiki User
∙ 14y ago
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How do you explain a car requires brakes in order to stop with law of motion?
try stopping a car without brakes!
When a vehicle is slowing down what changes its momentum and kinetic energy as force of brakes is an internal force?
Brakes absorb the kinetic energy in the form of heat and sometimes sound. When hot enough brakes can emit light.
How do you know if your brakes need replacing?
When you are driving slowly with your foot off the brakes you will hear a scraping noise. The noise will go away when you apply the brakes. What you are hearing is the wear indicators making contact with the rotor surface after the pad lining have worn down to a certain level. Not all brakes uses wear indicators. VBD
What are alloy brakes?
Alloy just means that the brakes aren't mad out of one pure metal, but rather of a homogenous mixture of metals - an alloy.
If only external force can change the velocity of a body how can the internal force of the brakes bring a car to rest?
It is not the force of the brakes that is stopping the car but rather external force of friction between tires and the road. Notice that no matter what the force at the brakes is, the car won't stop if there is no friction there(ie. the road is slippery). This is an excellent question. Consider the NASA space shuttle. It has brakes, yet the brakes work only on the ground - only while the shuttle is landing. Why? In space, the brakes have nothing to react against. So, as the questioner suspects, the internal forces of the brakes alone are not sufficient to change the velocity of the space shuttle. But once the shuttle lands, and is rolling down the runway, applying the brakes creates friction between the wheels and the runway. And it is the external force of the runway pushing back against the braking wheels that causes the shuttle to slow down.
How do antilock brakes or ABS increase the braking force while stopping and what μ value does this represent?
Antilock brakes do not increase the braking force.
How can you reduce and increase friction?
Lubrication to reduce friction. To increase friction step on the brakes.
When you apply the brakes on your bike you are clamping down on the bikes wheel to increase the force of?
You increase the friction.
What happens to the temperature of a cars brakes when they are applied?
They get hot.
What can increase braking distance?
Poor brakes and bald tyres
Why brake fluid should kept in an airtight container?
brake fluid absorbs moisture thus brings the boiling point of your brake fluid down to a much lower temperature. if your brake fluid reaches this temperature you can loose your brakes temporally. also the moisture in the fluid will cause highly unwanted corrosion of internal parts of your brake system.
Are disc's brakes the same as drum brakes?
No. Drum brakes are large and contain the mechanism within them. Disc brakes are slim and use calipers to slow them down. Although both are very similar, disc brakes are more advanced and a better option for your car.
To dry wet brakes what should you do what?
you should gently press the brake pedal and gently press the gas pedal, the increase friction will dry the brakes.....
How do you decrease velocity of a moving car?
You increase the frictional force by applying the brakes.
Does fanning air brakes cause air pressure to increase?
No you lose air pressure .
Does two foot braking increase the amount of force applied to the brakes?
It takes more effort to stop a car that does not have power brakes, although its rare to see a car without power brakes any longer. In either case, the literal answer to your question is yes it does increase the force applied to the brakes. Two feet are stronger than one. More force on the pedal translates to more force on the brake pads.
How can you increase braking distance?
By reducing the coefficient of friction between the brakes and the wheel OR between the road and the wheels.
