To find the velocity of the cat 4 seconds ago, we need to calculate its initial velocity (u). We can use the equation of motion:
v = u + at
Where:
- v is the final velocity (13 m/s in this case).
- u is the initial velocity (which we want to find).
- a is the acceleration (400 cm/s^2 converted to m/s^2 is 4 m/s^2).
- t is the time interval (4 seconds).
Rearranging the equation, we have:
u = v - at
Plugging in the values:
u = 13 m/s - (4 m/s^2 × 4 s) u = 13 m/s - 16 m/s u = -3 m/s
Therefore, the velocity of the cat 4 seconds ago was -3 m/s. The negative sign indicates that the cat was moving in the opposite direction at that time.