Question

a bus starting from rest attains a velocity of 84 km/h in 6 mins find acceleration

Answer 1

U=0
V=84km/h=1km=1000 m =84000
T=6 mins=360 secs
A=?
V=u +at
84000=0+360a
84000/360=a
233.33m/s²=a
Hope it will help u thx

Answer 2

$\blue{\bold{\underline{\underline{Answer:}}}}$

$\green{\therefore \text{Acceleration=19.79km/min}^{2}}$

$\orange{\bold{\underline{\underline{Step-by-step\:explanation:}}}}$

• In the given question information given about a bus which is in rest and after 10 sec it attains a velocity of 84 km/h.

• So, we have to find the acceleration of the bus.

$\green{\underline \bold{Given : }} \\ :\implies \text{Initial \: velocity(u) = 0 \: m} {s}^{ - 1} \\\\: \implies \text{Final \: velocity(v) = 84 \: km} {h}^{ - 1} \\ \\:\implies \text{Time(t) = 6 \: min} \\ \\ \red{\underline \bold{To \: Find : }}\\ \\ :\implies \text{Acceleration(a) = ?}$

•According to given question :

$:\implies v = 84\: km {h}^{ - 1} \times \frac{5}{18} \\\\\bold{first \: method : } \\\\ \bold{By \: third \: equation \: of \: motion} \\\\ :\implies s = ut + \frac{1}{2} a {t}^{2} \\\\ :\implies s = 0 \times 6 + \frac{1}{2} \times a \times {6}^{2} \\\\ \bold{:\implies s = \frac{36a}{2}} - - - - - (1) \\\\ \bold {By \: second\: equation \: of \: motion} \\\\ :\implies {v}^{2} = {u}^{2} + 2as - - - - - (2) \\\\ \bold{putting \: value \: of \: s \: in \: (2)} \\\\ : \implies { (84) }^{2} = {0}^{2} + 2 \times a \times \frac{36a}{2} \\\\ :\implies 7056 = 18 ({a})^{2} \\\\ :\implies {a}^{2} = \frac{7056}{18 } \\\\ :\implies {a}^{2} = 392 \\\\ : \implies a =\sqrt{392} \\\\\bold{:\implies a = 19.79 km/ {min}^{2} }$