Question

Work done of frictional force from instant ​

Answer 1

Answer:

• $-100\ J$

Step-by-step explanation:

1. Find acceleration:

• $m=2\ kg$
• $F=-5\ N$
• $a=\frac{F}{m}$  (Newton's second law)
• $a=\frac{-5}{2} =-2.5\ \frac{m}{s^{2}}$

2. Find distance traveled:

• $v_0=10\ \frac{m}{s}$
• $v=0$

• $a=-2.5\ \frac{m}{s^{2} }$
• $v^2-v_0^2=2ad$ (Kinematic equation)
• $-100=-5d$
• $d=20\ m$

3. Find work done by friction:

• $W=Fd$ (Work formula when angle between Force and Displacement vectors are 0°)
• $W=-5\times20=-100\ J$