Question 142: Motion in 1D

Question

A particle covers half of its total distance with speed v1 and the rest half distance with speed v2. Its average speed during the complete journey is

Accepted Answer

Let total distance = 2S
Let particle take t
1
time to cover first S distance,
$$ 	herefore $$ t
1
= $${S \over {{v_1}}}$$
Let particle take t
2
time to cover last S distance,
$$ 	herefore $$ t
2
= $${S \over {{v_2}}}$$
$$ 	herefore $$ Average speed = $${{2S} \over {{S \over {{v_1}}} + {S \over {{v_2}}}}}$$ = $${{2{v_1}{v_2}} \over {{v_1} + {v_2}}}$$

Answer

$${{{v_1} + {v_2}} \over 2}$$

Answer

$${{{v_1}{v_2}} \over {{v_1} + {v_2}}}$$

Answer

$${{2{v_1}{v_2}} \over {{v_1} + {v_2}}}$$

Answer

$${{v_1^2v_2^2} \over {v_1^2 + v_2^2}}$$

Motion in 1D

A particle covers half of its total distance with speed v1 and the rest half distance with speed v2. Its average speed during the complete journey is

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