Two identical toy cars

PHYSICS · Single correct · A Level · Physics · Mechanics and materials · Mechanics and materials

Problem

Two identical toy cars, each of mass

1.5\,\text{kg}

, are pushed from rest on a smooth floor. Car P receives

36\,\text{J}

of work, while car Q receives

18\,\text{J}

. What is the ratio of their final speeds

v_P : v_Q

? (a)

2:1

(b)

1:1

(c)

\sqrt{2}:1

(d)

1:\sqrt{2}