An object travels North at $4 \frac{m}{s}$ $4 m/s$ for $7 s$ $7 s$ and then travels South at $2 \frac{m}{s}$ $2 m/s$ for $4 s$ $4 s$ . What are the object's average speed and velocity?

Question

1152 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2017-06-17T05:50:19

The average speed is $= 3.27 m s^{- 1}$ $=3.27ms^-1$
The average velocity is $= 1.82 m s^{- 1}$ $=1.82ms^-1$

The average speed is $=$ $=$ total distance $/$ $/$ time,

The total distance is $d = (4 \cdot 7) + (2 \cdot 4) = 36 m$ $d=(4*7)+(2*4)=36m$

The total time is $t = 7 + 4 = 11 s$ $t=7+4=11s$

The average speed is $= \frac{d}{t} = \frac{36}{11} = 3.27 m s^{- 1}$ $=d/t=36/11=3.27ms^-1$

The average velocity is $=$ $=$ displacement $/ t i m e$ $/time$

$barv=(Deltax)/(t)=(7*4-2*4)/(7+4)=20/11=1.82ms^-1$

An object travels North at 4 m/s4ms 4 m/s for 7 s7s7 s and then travels South at 2 m/s2ms 2 m/s for 4 s4s 4 s. What are the object's average speed and velocity?