Question

could you help with question 5. Your solutions to the word problems in volving Newton's Laws should have the following features:Each solution should begin with one or more free body diagrams with a sign convention.The solution process should follow the GRASP process.Formulae should always be used in a three-step process: formula with letter variables, substitution of values, and then the answer.Answers should be expressed with the correct number of significant digits and with the direction if required.

Answer 1

ANSWER:

(a) 20 m/s^2

(b) 250 m

STEP-BY-STEP EXPLANATION:

Given:

Mass (m) = 250 g = 0.25 kg

Force (F) = 20 N

Frictional force (Ff) = 15 N

(a)

The net force on the block is:

$\begin{gathered} F_{net}=F-F_f \\ F_{net}=20-15 \\ F_{net}=5\text{ N} \end{gathered}$

We know that:

$\begin{gathered} F=m\cdot a \\ \text{ We replacing} \\ 5=0.25\cdot a \\ a=\frac{5}{0.25} \\ a=20\text{ m/s}^2 \end{gathered}$

(b)

We can calculate the partial distance from the following equation:

initial velocity (u) = 0 (start from rest)

$\begin{gathered} s=ut+\frac{1}{2}at^2 \\ \text{ we replacing} \\ s=0\cdot5+\frac{1}{2}\cdot20\cdot5^2 \\ s=250\text{ m} \end{gathered}$