Question

A horse running at 3 m/s speeds up with a constant acceleration of 5 m/s2. How fast is the
horse going when it travels 15.3 m from where it started to accelerate.

Answer 1

Answer:

The horse is going at 12.72 m/s speed.

Explanation:

The initial speed of the horse (u) = 3 m/s

The acceleration of the horse (a)= 5 m/$s^{2}$

The displacement( it is assumed it is moving in a straight line)(s)= 15.3 m

Applying the second equation of motion to find out the time,

$s=ut+\frac{1}{2}at^{2}$

$15.3=3t+2.5t^{2}$

$2.5t^{2}+3t-15.3=0$

Solving this quadratic equation, we get time(t)=1.945 s, the other negative time is neglected.

Now applying first equation of motion, to find out the final velocity,

$v=u+at$

$v=3+1.945*5$

$v=3+9.72$

v=12.72 m/s

The horse travels at a speed of 12.72 m/s after covering the given distance.