Question

Which car has the most kinetic energy? A car of mass 1500 kg with speed 5 m/s or A car of mass 1300 kg with speed 3 m/s or a car of mass 1200 kg with speed 2 m/s or a car mass 1400 kg with speed 4 m/s

Answer 1

The formula to find the kinetic energy of an object is:

KE = 1/2 MV^2 

So if we plug in the information 
1/2 x 1500 x 5^2
1/2 x 1500 x 25
750 x 25
 Car 1 has a KE of 18750

If needed you can find the other three on your own. It'd be good practice.

The answer is car 1.

Answer 2

Answer:

The first car has the most kinetic energy.

Explanation:

Given that,

For first car

Mass of car = 1500 kg

Speed of car = 5 m/s

For second car

Mass of car = 1300 kg

Speed of car = 3 m/s

For third car

Mass of car = 1200 kg

Speed of car = 2 m/s

For fourth car

Mass of car = 1400 kg

Speed of car = 4 m/s

The kinetic energy is defined as,

$K.E=\dfrac{1}{2}mv^2$

Where, m = mass

v = velocity

The kinetic energy of first car,

$K.E =\dfrac{1}{2}\times1500\times(5)^2$

$K.E=18750\ J$

The kinetic energy of second car,

$K.E =\dfrac{1}{2}\times1300\times(3)^2$

$K.E=5850\ J$

The kinetic energy of third car,

$K.E =\dfrac{1}{2}\times1200\times(2)^2$

$K.E=2400\ J$

The kinetic energy of fourth car,

$K.E =\dfrac{1}{2}\times1400\times(4)^2$

$K.E=11200\ J$

Therefore, The first car has 18750 J kinetic energy.

Hence, The first car has the most kinetic energy.