Question

Pls answer...... ...... .​

Answer 1

$\huge{\underline{\underline{\rm{AnsWer:-}}}}$

$\huge{\bf{70\:m/s}}$

$\huge{\underline{\underline{\rm{ExplainaTion:-}}}}$

a)

$\bf{Given}\begin{cases}\sf{Initial\:velocity (u)=0ms^{-1}}\\ \ \sf{Distance=20\:m}\\ \ \sf{Time=2s}\end{cases}$

a=?

using second equation of motion

s= ut+1/2at²

putting the values;

${ \tt{20 = 0 + \frac{1}{2}a(2) {}^{2} }} \\ \\ { \tt{20 = 2a}} \\ \\ { \tt{a = \frac{{ \cancel{20}}}{ \cancel{2} }}} \\ \\ { \bf{a = 10 \: ms {}^{ - 2} }}$

Now, we know the acceleration is uniform therefore by using 1st equation of motion

v= u+at

${ \sf{v = 0 + 10 \times 7}} \\ \\{ \boxed{ \bf{ v = 70 \: ms {}^{ - 1}}}}$

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b)

★Rate of change of velocity is called acceleration. In Uniform circular motion direction changes periodically due to which velocity also changes with time. Hence it is called accelerated motion. Eg. A cyclist moving around circular track with uniform speed.

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