BM Sharma Solutions for Chapter: Motion in Two Dimensions, Exercise 4: DPP

A person aiming to reach the exactly opposite point on the bank of a stream is swimming with a speed of $0.5 \mathrm{m} {\mathrm{s}}^{-1}$, at an angle of $120°$ with the direction of the flow of water. The speed of water in the stream is

A boat crosses a river with a velocity of $8 \mathrm{km} {\mathrm{h}}^{-1}$. If the resultant velocity of the boat is $10 \mathrm{km} {\mathrm{h}}^{-1}$, then the velocity of river water is,

A man, sitting in a bus, traveling in a direction from west to east, with a speed of $40 \mathrm{km} {\mathrm{h}}^{-1}$, observes that the rain drops are falling vertically down. To another man, standing on the ground, the rain will appear

A boat is rowed across a river at a rate of $4.5 \mathrm{km} {\mathrm{hr}}^{-1}$. The river flows at the rate of $6 \mathrm{km} {\mathrm{hr}}^{-1}$. The velocity of the boat in $\mathrm{m} {\mathrm{s}}^{-1}$ is

A swimmer crosses a river, along the line making an angle of $45°$ with the direction of flow. The velocity of the river water is $5 \mathrm{m} {\mathrm{s}}^{-1}$. The swimmer takes $12 \mathrm{seconds}$ to cross the river of width $60 \mathrm{m}$. The velocity of the swimmer with respect to water, will be

A jet aeroplane travelling from east to west at a speed of $500 \mathrm{km} {\mathrm{h}}^{-1}$ ejects out gases of combustion at a speed of $1500 \mathrm{km} {\mathrm{h}}^{-1}$ with respect to the jet plane. What is the velocity of the gases with respect to an observer on the ground?

Rain is falling vertically with a velocity of $3 \mathrm{km} {\mathrm{h}}^{-1}$. A man walks in the rain with a velocity of $4 \mathrm{km} {\mathrm{h}}^{-1}$. The raindrops will fall on the man with a velocity of

A man who can swim at a rate of $2 \mathrm{km} {\mathrm{h}}^{-1}$ in still river crosses a river to a point exactly opposite on the other bank by swimming in the direction $120°$ to the flow of the water in the river. The velocity of the water current in $\mathrm{km} {\mathrm{h}}^{-1}$ is