Question

A 1890 kg truck traveling north at 34 km/h turns east and accelerates to 62 km/h. (a) What is the change in the truck's kinetic energy

Answer 1

2540.18 kJ

Step-by-step explanation:

The change in the trucks kinetic energy is same as the net work done by the truck in covering the said distance

Given data

mass of truck m= 1890 kg

initial velocity of truck u1= 34 km/h

final velocity v1= 62 km/h

applying the kinetic energy formula we have

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

K.E(initial)

`K.E(initial)= (1)/(2)*1890*34^2\\\\ K.E(initial)= (1)/(2)*1890*1156\\\\ K.E(initial)= (1)/(2)*2184840\\\\ K.E(initial)= 1092420J\\\\\ K.E(initial)= 1092.4kJ`

K.E(final)

`K.E(initial)= (1)/(2)*1890*62^2\\\\ K.E(initial)= (1)/(2)*1890*3844\\\\ K.E(initial)= (1)/(2)*7265160\\\\ K.E(initial)= 3632580J\\\\\ K.E(initial)= 3632.58kJ`

The change in K.E= K.E(final)- K.E(initial) = 3632.58-1092.4= 2540.18 kJ

the change in the truck's K.E is 2540.18 kJ