A train is travelling at a speed of 90 kmh–1.
[question] Question. A train is travelling at a speed of 90 kmh–1. Brakes are applied so as to produce a uniform acceleration of – 0.5 ms–2. Find how far the train will go before it is brought to rest. [/question] [solution] Solution: Given, initial speed of train, $\mathrm{u}=90 \mathrm{~km} \mathrm{~h}^{-1}=90 \times \frac{5}{18}=25 \mathrm{~ms}^{-1}$ Final speed, $\mathrm{v}=0 \mathrm{~ms}^{-1}$, Acceleration, $\mathrm{a}=-0.5 \mathrm{~ms}^{-2}$, Distance covered, $\mathrm{s}=$ ? Using the re...
A bus starting from rest moves with a uniform acceleration
[question] Question. A bus starting from rest moves with a uniform acceleration of $0.1 \mathrm{~ms}^{-2}$ for 2 minutes. Find (a) the speed acquired. (b) the distance travelled. [/question] [solution] Solution: Given Initial speed of bus, $\mathrm{u}=0 \mathrm{~ms}^{-1}$ Final speed of bus, $v=$ ? $\mathrm{a}=0.1 \mathrm{~ms}^{-2}, \mathrm{t}=2 \mathrm{~min}=120 \mathrm{~s}$ $\mathrm{s}=$ ? (i) We know, $\mathrm{v}=\mathrm{u}+\mathrm{at}$ or $\mathrm{v}=0+0.1 \times 120=12 \mathrm{~ms}^{-1}$ (i...