Why a boatman exists a force on water with his oars in the opposite direction to move forward ?

What happens when force acting on an object are in opposite direction and equal?

A 2 kg ball moving at 24 ms undergoes inelastic head on collision with a 4 kg ball moving in the opposite direction at 48 ms. If the coefficient of restitution is 2/3, their velocities in ms-after impact are

Give examples of a one-dimensional motion where the particle moving along positive x-direction comes to rest periodically and moves forward.

Form the pair of linear equations in the following problems and find their solutions (if they exist) by any algebraic method :-Places A and B are 80 km apart from each other on a highway. A car starts from A and another from B at the same time. If they move in the same direction they meet in 8 hours , and if they move in opposite direction, they meet in 1 hour and 20 minutes respectively. Find the speed of the cars.

A and B are two points of 150 km apart on a highway. A car starts from A and another from B at the same time. If they move in the same direction, they meet in 15 hours, but if they move in opposite direction, they meet in one hour. Find their speeds.

A uniform magnetic field of 1.5 T exists in a cylindrical region of radius10.0 cm, its direction parallel to the axis along east to west. A wire carrying current of 7.0 A in the north to south direction passes through this region. What is the magnitude and direction of the force on the wire if, the wire intersects the axis.