A toy rocket of mass is launched straight upward from rest

PHYSICS · Single correct · CBSE · Physics · Laws of Motion · Laws of Motion

Problem

A toy rocket of mass

0.40\,\text{kg}

is launched straight upward from rest. During the first

2.0\,\text{s}

its engine produces a constant upward thrust of

4.0\,\text{N}

. Neglect air resistance. What is the rocket’s upward speed at the instant the engine stops? (a)

0.20\,\text{m/s}

(b)

8.0\,\text{m/s}

(c)

0.40\,\text{m/s}

(d)

9.8\,\text{m/s}