Between two stations a train accelerates uniformly at first, then moves with constant velocity and f

English

Gujarati

Hindi

2.Motion in Straight Line

hard

Between the two stations a train accelerates uniformly at first, then moves with constant velocity and finally retards uniformly. If the ratio of the time taken be $1 : 8 : 1$ and the maximum speed attained be $60\,km/h,$ then what is the average speed over the whole journey.......$km/h$

$48$

$52$

$54$

$56$

Solution

$A$ ve. speed $=\begin{array}{ll}{\text { total distance }} & {\text { area under } v-\text { t graph }} \\ {\text { total time }} & {\text { totaltime }}\end{array}$

$=\frac{\frac{1}{2}(8 t+10 t) \times 60}{10 t}=54 k m / h r$

average speed for $A$ to $B=\frac{0+60}{2}=30 \mathrm{km} / \mathrm{hr}$

average speed for $C$ to $D=\frac{60+0}{2}=30 \mathrm{km} / \mathrm{hr}$

average speed for $A$ to $D$

$v_{\operatorname{arc}}=\frac{30 \times t+60 \times 8 t+30 \times t}{t+8 t+t}$

$=\frac{30+480+30}{10}=\frac{540}{10}=54 \mathrm{km} / \mathrm{hr}$

Standard 11

Physics

If a car covers $2/5^{th}$ of the total distance with $v_1$ speed and $3/5^{th}$ distance with $v_2 $ then average speed is

medium

A point traversed half of the distance with a velocity $v_0$. The remaining part of the distance was covered with velocity $v_1$ for half the time and with velocity $v_2$ for the other half of the time. The mean velocity of the point averaged over the whole time of motion is

medium

A car covers $A B$ distance with first one-third at velocity $v _{1} ms ^{-1}$, second one-third at $v _{2} ms ^{-1}$ and last one-third at $v _{3} ms ^{-1}$. If $v _{3}=3 v _{1}, v _{2}=2 v _{1}$ and $v _{1}=11\,ms ^{-1}$ then the average velocity of the car is________ $ms ^{-1} .$

medium

(JEE MAIN-2022)

Write relation between speed and magnitude of velocity.

medium

Velocity of an object in rectilinear motion is given as function of time by $v = t -t^3$, where $v$ is in $m/s$ and $t$ is in seconds. Its average velocity over the time interval from $t = 0\ s$ to $t = 2\ s$ is……..$m/s$

hard

Between the two stations a train accelerates uniformly at first, then moves with constant velocity and finally retards uniformly. If the ratio of the time taken be $1 : 8 : 1$ and the maximum speed attained be $60\,km/h,$ then what is the average speed over the whole journey.......$km/h$

Solution

Similar Questions

If a car covers $2/5^{th}$ of the total distance with $v_1$ speed and $3/5^{th}$ distance with $v_2 $ then average speed is

A point traversed half of the distance with a velocity $v_0$. The remaining part of the distance was covered with velocity $v_1$ for half the time and with velocity $v_2$ for the other half of the time. The mean velocity of the point averaged over the whole time of motion is

A car covers $A B$ distance with first one-third at velocity $v _{1} ms ^{-1}$, second one-third at $v _{2} ms ^{-1}$ and last one-third at $v _{3} ms ^{-1}$. If $v _{3}=3 v _{1}, v _{2}=2 v _{1}$ and $v _{1}=11\,ms ^{-1}$ then the average velocity of the car is________ $ms ^{-1} .$

Write relation between speed and magnitude of velocity.

Velocity of an object in rectilinear motion is given as function of time by $v = t -t^3$, where $v$ is in $m/s$ and $t$ is in seconds. Its average velocity over the time interval from $t = 0\ s$ to $t = 2\ s$ is……..$m/s$

Start a Free Trial Now