A cyclist rides 8.0 km east for 20 minutes, then he turns and heads west for 8 minutes and 3.2 km. Finally, he rides east for 16 km, which takes 40 minutes. (a) What is the final displacement of the cyclist? (b) What is his average velocity?

a) final displacement of the cyclist = 20.8km

b) average velocity = 18 .35km/hr

Explanation:

Given that,

cyclist rides 8.0 km east for 20 minutes

heads west for 8 minutes and 3.2 km

rides east for 16 km, which takes 40 minutes

The cyclist has 3 vector

v₁ = 8i km

v₂ = -3.2i km

v₃ = 16i km

The final isplacement is the sum of vector

= 8 + (-3-2) + 16

= 20.8km

final displacement of the cyclist = 20.8km

b) average velocity we have

average velocity = 18 .35km/hr

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the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia