Question

Which has more kinetic energy, a small sports car traveling at 30 km/hr or a large tractor-trailer traveling at 75 km/hr?

Answer 1

Step-by-step explanation:

Kinetic energy is the energy of a substance or object due to the motion of its particles.

Mathematically, K.E =
`(1)/(2)mv^(2)`

Therefore, more is the velocity of an object more will be its kinetic energy.

Since velocity of a large tractor-trailer is 75 km/hr, therefore, its kinetic energy will be more than the kinetic energy of given small sports car.

Answer 2

Large tractor-trailer traveling at 75 km/hr will have more kinetic energy.

Step-by-step explanation:

Kinetic energy is defined as the energy of an object due to its motion. It generally depends upon the mass and velocity of the object.

`K.E=(1)/(2)mv^2`

Both mass and velocity of the object are directly proportional to the kinetic energy of the object.

Mass of a sports car in comparison to large tractor-trailer is small.

`m_(car)<m_(truck)`

Also given that velocity of car is 35 km/hr and velocity of truck is 75 km/hr.

`v_(car)<v_(truck)`

As we can see that both the mass and velocity of the truck is greater which means that kinetic energy possessed by the truck will be more than that if the car.

`K.E_(car)<K.E_(truck)`

`(1)/(2)m_(car)v_(car)^2<(1)/(2)m_(truck)v_(truck)^2`