Question

You’re riding a unicorn at 25 m/s and come to a uniform stop at a red light 20 m away. What’s your acceleration?

Answer 1

Assuming that the unicorn and rider come to a stop uniformly (i.e., with constant acceleration), we can use the following kinematic equation to calculate the acceleration:

v^2 = u^2 + 2as

where:

v is the final velocity (0 m/s, since the unicorn comes to a stop)

u is the initial velocity (25 m/s, the speed of the unicorn and rider)

a is the acceleration (what we're trying to find)

s is the distance traveled (20 m)

Plugging in the known values, we get:

0^2 = (25 m/s)^2 + 2a(20 m)

Simplifying and solving for a, we get:

a = - (25 m/s)^2 / (2 x 20 m) = -31.25 m/s^2

The negative sign indicates that the acceleration is in the opposite direction to the initial velocity (i.e., deceleration). Therefore, the acceleration of the unicorn and rider as they come to a stop is 31.25 m/s^2.

Answer 2

15.625 m/s^2

Step-by-step explanation:

To find the acceleration, we can use the kinematic equation:

v^2 = u^2 + 2as

v = final velocity (which is 0 m/s since you come to a stop)

u = initial velocity (25 m/s)

a = acceleration (unknown in this case)

s = distance traveled (20 m)

Plugging in the values, we get:

0^2 = (25)^2 + 2a(20)

Solving for a:

625 = 40a

a = 625/40 = 15.625 m/s^2

So, your acceleration when coming to a stop would be approximately 15.625 m/s^2.