Question 148: Motion in 1D

Question

A particle moves in a straight line with a constant acceleration. It changes its velocity from 10 ms$$-$$1 to 20 ms$$-$$1 while passing through a distance 135 m in t second. The value of t is

Accepted Answer

v
2
= u
2
+ 2$$a$$s
$$ \Rightarrow $$ $$a = {{{v^2} - {u^2}} \over {2s}}$$
= $${{{{\left( {20} ight)}^2} - {{\left( {10} ight)}^2}} \over {2 	imes 135}}$$
= $${{400 - 100} \over {270}}$$
= $${{300} \over {270}}$$
= $${{10} \over 9}$$ m/s
2
$$v = u + at$$
$$ \Rightarrow $$ $$t = {{v - u} \over a}$$
= $${{20 - 10} \over {{{10} \over 9}}}$$
= $${{10} \over {{{10} \over 9}}}$$ = 9 m/s

Answer

12

Answer

9

Answer

10

Answer

1.8

Motion in 1D

A particle moves in a straight line with a constant acceleration. It changes its velocity from 10 ms$-1 to 20 ms-$1 while passing through a distance 135 m in t second. The value of t is

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