Question

A car traveling at 60 mph has how much more energy than a car going at 15 mph? KE increases by a factor of _____. 4 1/4 16 1/16

Answer 1

KE increases by the square of the speed.  Since the first car is moving 4 times faster, its KE is 16 times higher

Answer 2

Answer with explanation:

Kinetic Energy of a body is given by the formula

`=(mv^2)/(2)`

Kinetic Energy of Car having speed 60 mph

`\rightarrow K.E_(1)=(m * (60)^2)/(2)\\\\=1800 m`

Kinetic Energy of Car having speed 15 mph

`\rightarrow K.E_(2)=(m * (15)^2)/(2)\\\\=(225 m)/(2)`

`\Rightarrow(K.E_(1))/(K.E_(2))=(1800)/((225)/(2))\\\\=8 * 2\\\\=16`

Kinetic energy of Car Traveling at 60 mph has 16 times more energy than a car going at 15 mph.