Answer:

Explanation:
m = Mass of object = 
mg = Weight of object = 20 N
g = Acceleration due to gravity = 
v = Final velocity = 15 m/s
u = Initial velocity = 0
d = Distance moved by the object = 150 m
= Angle of slope = 
f = Force of friction
fd = Work done against friction
The force balance of the system is

The work done against friction is
.
Answer:
a) t = 4.16 s
b) x = 141.51 m
Explanation:
Given
v = 21.5 m/s
x0 = 52.0 m
a = 6.0 m/s²
a) Motorcycle
x = v0*t + (a*t²/2)
x = 21.5t + (6*t²/2)
x = 21.5t + 3t² <em>(I)</em>
Car
x = x0 + v0*t
x = 52 + 21.5t <em>(II)</em>
<em />
then we can apply <em>I = II</em>
21.5t + 3t² = 52 + 21.5t
⇒ 3t² = 52
⇒ t = 4.16 s
b) We can use <em>I</em> or <em>II</em>, then
x = 52 + 21.5*(4.16)
⇒ x = 141.51 m
<span>B. equal and in opposite directions</span>
Explanation:
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