Question

भाई लोग बता दो। physics.​

Answer 1

Answer:

See answer in above picture

Answer 2

$\sf{\large{\underline{\underline{EXPLANATION:}}}}$

$\textbf{\underline{\underline{Question 2,,}}}</p><p>$

$\textbf{\underline{For 1st equation of motion,,}}</p><p>$

$\mathtt{\boxed{\blue{v=u+at}}}$

As we know,,

$\mathtt{\boxed{a=\frac{v-u}{t}}}$

therefore,,

$\mathtt{\boxed{\blue{v=u+at...(1)}}}$

$\textbf{\underline{For 2nd equation of motion,,}}</p><p>$

$\mathtt{\boxed{\blue{s=ut+\frac{1}{2}at^{2}}}}$

Using calculus,

since,we know,,

$\sf{\boxed{v=\frac{ds}{dt}}}$

$\sf{\implies{ds=vdt}}$

Integrating both sides,,

$\sf{\implies{\int_0^s{ds}=\int_0^t{v\,dt}}}$

$\sf{\implies{[s]_0^s=\int_0^t{(u+at)\,dt}}}$

$\sf{\implies{s-0=\int_0^t{u\,dt}\int_0^t{at\,dt}}}$

$\sf{\implies{s-0=u\int_0^t{\,dt}+a\int_0^t{t\,dt}}}$

$\sf{\implies{s=[t]_0^t+a[\frac{t^{2}}{2}]_0^t}}$

$\sf{\implies{s= u(t-0)+a(\frac{t^{2}}{2}-\frac{0^{2}}{2})}}$

$\sf{\implies{s= ut+\frac{at^{2}}{2}}}$

Therefore,,

$\mathtt{\boxed{\blue{s=ut+\frac{1}{2}at^{2}.......(2)}}}$

$\textbf{\underline{For 3rd equation of motion,,}}</p><p>$

$\mathtt{\boxed{\blue{v^{2}-u^{2}=2as}}}$

Using calculus,,

since we know,,

$\sf{\boxed{a=\frac{dv}{dt}}}$

$\sf{\implies{a=\frac{dv}{dt}\times{\frac{ds}{ds}}}}$

$\sf{\implies{a=\frac{dv}{ds}\times{\frac{ds}{dt}}}}$

$\sf{\implies{a=\frac{dv}{ds}\times{v}}}$

$\sf{\implies{ads=vdv}}$

Integrating both sides,,

$\sf{\implies{\int_0^s{a\,ds}=\int_u^v{v\,dv}}}$

$\sf{\implies{a\int_0^s{ds}=[\frac{v^{2}}{2}]_u^v}}$

$\sf{\implies{a[s]_0^s=\frac{v^{2}}{2}-\frac{u^{2}}{2}}}$

$\sf{\implies{a[s-0] = \frac{v^{2}-u^{2}}{2}}}$

$\sf{\implies{as = \frac{v^{2}-u^{2}}{2}}}$

$\sf{\implies{2as = v^{2}-u^{2}}}$

Therefore,,

$\mathtt{\boxed{\blue{v^{2}-u^{2}=2as</strong><strong>.</strong><strong>.</strong><strong>.</strong><strong>(</strong><strong>3</strong><strong>)</strong><strong>}}}$

$\rule{200}2$

$\textbf{\underline{\underline{Question 3,,}}}</p><p>$

$\sf{Given}\begin{cases}\sf{a=5ms^{-2}}\\ \sf{u=0ms^{-1}}\\ \sf{t=20s}\\ \sf{then,s=??}\end{cases}$

$\textbf{\underline{Using 2nd equation of motion,,}}</p><p>$

$\mathtt{\boxed{\blue{s=ut+\frac{1}{2}at^{2}}}}$

$\sf{\implies{s= 0t+\frac{1}{2}\times{5}\times{20^{2}}}}$

$\sf{\implies{s= \cancel\dfrac{2000}{2}}}$

$\sf{\implies{s=1000m=1km}}$

Therefore, distance covered,

s=1000m=1km

$\rule{200}2$

$\textbf{\underline{\underline{Question 4,,}}}</p><p>$

$\sf{Given}\begin{cases}\sf{a=10ms^{-2}}\\ \sf{u=0ms^{-1}}\\ \sf{t=5s}\\ \sf{then,s=??}\end{cases}$

$\textbf{\underline{Using 2nd equation of motion,,}}</p><p>$

$\mathtt{\boxed{\blue{s=ut+\frac{1}{2}at^{2}}}}$

$\sf{\implies{s= 0t+\frac{1}{2}\times{10}\times{5^{2}}}}$

$\sf{\implies{s= \cancel\dfrac{250}{2}}}$

$\sf{\implies{s=125m}}$

Therefore, distance covered,

s=125m

$\rule{200}2$

$\textbf{\underline{\underline{Question 5,,}}}</p><p>$

$\sf{Given}\begin{cases}\sf{a=-2cms^{-2}}\\ \sf{u=0ms^{-1}}\\ \sf{t=3s}\\ \sf{then,v=??}\end{cases}$

$\textbf{\underline{Using 1st equation of motion,,}}</p><p>$

$\mathtt{\boxed{\blue{v=u+at}}}$

$\sf{\implies{v=0+(-2)3}}$

$\sf{\implies{v=-6cms^{-1}}}$

$\rule{200}2$

Hope it helps ❣️❣️❣️