Question

At the end of the school day, student A and student B say goodbye and head in opposite directions, walking at constant rates. Student B heads west to the bus stop, while student A walks east to her house. After 3.0 min, student A is 300 m east and student B is 450 m west. Assuming east to be the positive direction, the velocities in m/s of student A and student B are:

• A. +1.67 m/s; -2.5 m/s
• B. +1.67 m/s; +2.5 m/s
• C. +2.5 m/s; -1.67 m/s
• D. -1.67 m/s; +2.5 m/s

Answer 1

The correct option is A +1.67 m/s; -2.5 m/s

$\text{velocity}=\frac{\text{displacement}}{\text{time}}$

$v_A=\frac{300m}{180s}=+1.67m/s$.

$v_B=\frac{450m}{180s}=-2.5m/s$.