Relative density, or specific gravity, is the ratio of the density of a substance to the density of a given reference material. Specific gravity for liquids is nearly always measured with respect to water at its densest; for gases, the reference is air at room temperature.
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>
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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
Part a
Answer: 17.58 km/h

Total Distance =10 km
Total time =0.5689 h

Part b
Answer: 17.626 km/h

Total Distance =42.195 km
Total time =2.3939 h

I think that this is false but I am not sure