# science

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a car of mass 1360 kg descends from a hill of height 86 m at a constant speed of 20 km/h. assuming that all the potential/kinetic energy of the car goes into heat in the brakes, find the rise in temperature of the brakes (use the heat capacity (C) of the brakes to be 16kJ/C and ignore any heat losses to the surroundings

• science -

Q=c*delta T

c=16

q=potential energy
potential energy=mgh
h=86
g=10
m=1360
Q/c = delta T
Delta T= 73.1 K

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