Question

.A body travelling along a straight line covers 20m in 4s and then 30m in 10s. Then the average speed for the entire journey is :​

Answer 1

Provided that:

• A body travelling along a straight line covers 20 metres in 4 seconds.

• And afterthat the body cover 30 metres in 10 seconds.

To calculate:

• Average speed

Solution:

• Average speed = 3.57 m/s

Using concept:

• Average speed formula

Using formula:

• ${\small{\underline{\boxed{\pmb{\sf{a_v \: = \dfrac{s_1 + s_2}{t_1 + t_2}}}}}}}$

Where, a_v denotes average speed, s_1 denotes distance one, s_2 denotes distance two, t_1 denotes time one and t_2 denotes time two.

Required solution:

$:\implies \sf a_v \: = \dfrac{s_1 + s_2}{t_1 + t_2} \\ \\ :\implies \sf a_v \: = \dfrac{20 + 30}{4 + 10} \\ \\ :\implies \sf a_v \: = \dfrac{50}{14} \\ \\ :\implies \sf a_v \: = \dfrac{25}{7} \\ \\ :\implies \sf a_v \: = 3.57 \: ms^{-1} \\ \\ :\implies \sf Average \: speed \: = 3.57 \: ms^{-1}$