Rain is falling vertically with a speed of 30 | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) Let the velocity of rain be $\vec{v}_r = -30\hat{j}\,ms^{-1}$ and the velocity of the bicycle be $\vec{v}_b = -12\hat{i}\,ms^{-1}$ (since she is m

Vedclass · Accepted Answer

At an angle of $	an^{-1} (\frac {2}{5})$ with the vertical towards the west

Vedclass · Answer

(B) Let the velocity of rain be $\vec{v}_r = -30\hat{j}\,ms^{-1}$ and the velocity of the bicycle be $\vec{v}_b = -12\hat{i}\,ms^{-1}$ (since she is moving from east to west).The relative velocity of rain with respect to the woman is $\vec{v}_{rb} = \vec{v}_r - \vec{v}_b = -30\hat{j} - (-12\hat{i}) = 12\hat{i} - 30\hat{j}\,ms^{-1}$.To protect herself from rain,she must hold the umbrella in the direction of the relative velocity of rain $\vec{v}_{rb}$.The angle $	heta$ with the vertical is given by $	an 	heta = \frac{|v_b|}{|v_r|} = \frac{12}{30} = \frac{2}{5}$.Thus,$	heta = 	an^{-1}(\frac{2}{5})$.Since the relative velocity vector has a positive $x$-component (eastward relative to the woman) and a negative $y$-component (downward),the rain appears to come from the east. Therefore,she must tilt her umbrella towards the west to block the rain.

Rain is falling vertically with a speed of $30\,ms^{-1}$. $A$ woman rides a bicycle with a speed of $12\,ms^{-1}$ in the east to west direction. She should hold her umbrella:

Similar Questions

The speed of a swimmer is $4\,km\,h^{-1}$ in still water. If the swimmer makes his strokes normal to the flow of a river of width $1\,km$,he reaches a point $750\,m$ downstream on the opposite bank. The speed of the river water is $.........\,km\,h^{-1}$.

Two trains, each $30 \,m$ long, are travelling in opposite directions with velocities $5 \,m/s$ and $10 \,m/s$. They will cross each other after: (in $\,s$)

Two particles $A$ and $B$ are moving in a horizontal plane as shown in the figure at $t = 0$. The time after which $A$ will catch $B$ is.......$s$.

$A$ man running at a speed of $5 \text{ km/h}$ finds that the rain falls vertically. When he stops running,he finds that the rain is falling at an angle of $60^{\circ}$ with the horizontal. The velocity of rain with respect to the running man is

Vedclass Test Series

Exam Paper Generator

Online Exam Module