Question

An athlete runs 150 m in 15 seconds, then turns around and jogs 50 m back towards starting point in 25 s.
What is his average speed and average velocity for total time? Assume he travels along the same straight line
always.​

Answer 1

Answer:

Average speed = 5m/s

Average Velocity = 2.5m/s

Explanation:

Given,

S1 = 150m

S2 = 50m

T1 = 15s

T2 = 25s

Now,

$average \: speed \: = \frac{total \: distance}{total \: time}$

So Average speed =

$\frac{s1 \: + s2}{t1 + \: t2}$

So Average speed = (150+50)/(25+15)

= 200/40

= 5m/s

And ,

$average \: velocity \: = \: \frac{total \: displacement}{total \: time}$

= (S1 + S2)/( T1 + T2)

=

$\frac{150 + ( - 50)}{25 + 15}$

( We took negative 50 as 50m displacement is in opposite direction of the positive sides which we always take as the right side and both displacement and velocity depends upon the direction)

=

$\frac{150 - 50}{40}$

=

$\frac{100}{40}$

= 2.5m/s