Question

1. a boat accelerates from 10 knots/hour to 5 knots/hr. in 10 minutes. what is the acceleration? 0.50 knots/hr./min -0.50 knots/hr./min -0.5 knots/hr./min 0.5 knots/hr./min

Explanation:

Step1: Identify initial and final velocities and time

Initial velocity $u = 10$ knots/hour, final velocity $v = 5$ knots/hour, time $t=10$ min. First convert time to hours since velocity is in knots/hour. 10 min $=\frac{10}{60}=\frac{1}{6}$ hours.

Step2: Use acceleration formula

The formula for acceleration $a=\frac{v - u}{t}$. Substitute $u = 10$, $v = 5$ and $t=\frac{1}{6}$ into the formula. $a=\frac{5 - 10}{\frac{1}{6}}$.

Step3: Calculate acceleration

$a=\frac{- 5}{\frac{1}{6}}=-30$ knots/hour. But we want the acceleration in knots/hour/min. Since 1 hour = 60 min, to convert the acceleration to knots/hour/min, divide by 60. $a=\frac{-30}{60}=- 0.5$ knots/hour/min.

Answer:

-0.5 knots/hour/min