Projectile incline

A person, reaches a point directly opposite on the other bank of a flowing river, while swimming at a speed of 5 m/s at an angle of 120^o with the flow. The speed of the flow must be

• 2.5 m/s

• 3 m/s

• 4 m/s

• 1.5 m/s

A boat streams in a river with velocity 2i+5j with respect to ground. The river water flows with a velocity of -3i-4j with respect to the ground. what is the relative velocity of boat w.r.t. river water ?

• i - j

• 9i + 7j

• -i + j

• 5i + 9j

A car with a vertical windshield moves in a rainstorm at a speed of 40 km/hr. The rain drops fall vertically with constant speed of 20 m/s. The angle at which rain drops strike the windshield is

 

• A

• B

• C

• D

• A

• B

• C

• D

• A

• B

• C

• D

• A

• B

• C

• D

• A

• B

• C

• D

• A

• B

• C

• D

• A

• B

• C

• D