Answer:
If an object is moving at a constant speed in a constant rightward direction, then the acceleration is zero and the net force must be zero.
Answer:

Explanation:
<h3><u>Given data:</u></h3>
Acceleration = a = 0.4 m/s²
Initial Speed =
= 20 m/s
Final Speed =
= 40 m/s
<h3><u>Required:</u></h3>
Time = t = ?
<h3><u>Formula:</u></h3>

<h3><u>Solution:</u></h3>
Rearranging formula for t
![\displaystyle t =\frac{V_f-V_i}{a} \\\\t = \frac{40-20}{0.4} \\\\t = \frac{20}{0.4} \\\\\boxed{t = 50 \ seconds}\\\\\rule[225]{225}{2}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20t%20%3D%5Cfrac%7BV_f-V_i%7D%7Ba%7D%20%5C%5C%5C%5Ct%20%3D%20%5Cfrac%7B40-20%7D%7B0.4%7D%20%5C%5C%5C%5Ct%20%3D%20%5Cfrac%7B20%7D%7B0.4%7D%20%5C%5C%5C%5C%5Cboxed%7Bt%20%3D%2050%20%5C%20seconds%7D%5C%5C%5C%5C%5Crule%5B225%5D%7B225%7D%7B2%7D)
Answer: Friction is a force that resists relative motion between two surfaces in contact. Depending on the application, friction may be desirable or undesirable.
87.8 , 31 Celsius=87.8(88) in Fahrenheit
-2 for O
-1 for F
0 for N2
+1 for Li
+3 for Fe