The stream of a river is flowing with a speed of \(2\,km/h.\) A swimmer can swim at a speed of \(4\,km/h.\) ....... \(^o\) should be the direction of the swimmer with respect to the flow of the river to cross the river straight .

Pick an option to check your answer.

Verified Solution

Answer & Solution

Correct Answer

(C) \(120\)

Step-by-step Solution

Detailed explanation

\(\begin{array}{l}
For\,swimmer\,to\,cross\,the\,river\,straight\\
\Rightarrow \,\,\,\,\,4\,\sin \,\theta = 2\\
\Rightarrow \,\,\,\,\,\sin \,\theta \, = \frac{1}{2}\, \Rightarrow \,\theta \, = {30^ \circ }\\
So,\,angle\,with\,direction\,of\,river\,flow\,\\
= {90^ \circ } + \theta = {120^ \circ }.
\end{array}\)

Same subject

A car accelerates from rest at a constant rate \(\alpha\) for some time after which it decelerates at a constant rate \(\beta\) to come to rest. If the total time elapsed is \(t\) seconds, the total distance travelled is

JEE Mains 2021 Hard
A thin bar of length \(L\) has a mass per unit length \(\lambda \), that increases linearly with distance from one end. If its total mass is \(M\) and its mass per unit length at the lighter end is \(\lambda_0\), then the distance of the centre of mass from the lighter end is

JEE Mains 2014 Hard
Energy released when two deuterons \(\left({ }_1 \mathrm{H}^2\right)\) fuse to form a helium nucleus \(\left({ }_2 \mathrm{He}^4\right)\) is :
(Given : Binding energy per nucleon of \({ }_1 \mathrm{H}^2=1.1 \mathrm{MeV}\) and binding energy per nucleon of \({ }_2 \mathrm{He}^4=7.0 \mathrm{MeV}\))

JEE Mains 2025 Easy
The height of victoria falls is \(63\, {m}\). What is the difference in temperature of water at the top and at the bottom of fall ? (In \(^{\circ} {C}\)) [Given \(1\, {cal}=4.2\, {J}\) and specific heat of water \(\left.=1 \,{cal} \,{g}^{-1}\;{ }^{\circ}\, {C}^{-1}\right]\)

JEE Mains 2021 Medium
Mass per unit area of a circular disc of radius \(\mathrm{a}\) depends on the distance \(\mathrm{r}\) from its centre as \(\sigma(\mathrm{r})=\mathrm{A}+\mathrm{Br} .\) The moment of inertia of the disc about the the axis, perpendicular to the plane and passing through its centre is

JEE Mains 2020 Hard
Identify the correct truth table of the given logical circuit.

JEE Mains 2026 Medium

Explore more questions on app

From JEE Mains

Region \(I\) and \(II\) are separated by a spherical surface of radius \(25\, {cm}\). An object is kept in region \(I\) at a distance of \(40\, {cm}\) from the surface. The distance of the image from the surface is \(.....\,cm\)

JEE Mains 2021 Medium
Applying the principle of homogeneity of dimensions, determine which one is correct. where \(\mathrm{T}\) is time period, \(\mathrm{G}\) is gravitational constant, \(M\) is mass, \(r\) is radius of orbit.

JEE Mains 2024 Hard

Explore more questions on app