What is its speed after 1.87 s if it accelerates uniformly at −4.31 m/s^2?

Answer in units of m/s

To find the speed of an object after a certain time if it accelerates uniformly, you can use the equation:

v = u + at

Where:
v = final velocity
u = initial velocity
a = acceleration
t = time

In this case, the acceleration is given as -4.31 m/s^2, which means it is directed in the opposite direction of the initial velocity, and the negative sign indicates that the object is decelerating.

Since the initial velocity (u) is not given in the question, we assume it to be zero. Therefore, the equation simplifies to:

v = 0 + (-4.31 m/s^2) * (1.87 s)

Now we can calculate the speed (v):

v = -4.31 m/s^2 * 1.87 s
v = -8.05297 m/s

Since speed is a scalar quantity, it only has magnitude and no direction. Thus, the speed after 1.87 s, when the object is decelerating uniformly at -4.31 m/s^2, is approximately 8.05 m/s.