Answer Happy

A river is 110 m wide and the water is flowing at a rate of 3 m/s. If it takes a swimmer 20 seconds to swim from one shore to a point directly across the river (the swimmer travels straight across the river) how fast can the swimmer swim? A) 4.47 m/s OB) 5.37 m/s OC) 6.26 m/s D) 7.16 m/s E) 8.05 m/s
F 2.5 kg Two blocks of masses m1 = 4.0 kg and m2 = 2.5 kg are placed in contact on a horizontal, frictionless surface, with the more massive block on the left. A force of magnitude F = 8.5 N, pointing to the right, is applied to the more massive block. What is the magnitude of the force that more massive block applies to the less massive block? OA) 3.3 N B) 4.9 N C) 6.5 N D) 8.2 N 4.0 kg E) 9.8 N
55 N 38⁰ A force of 55 N is applied downward at an angle of 38 degrees with respect to the horizontal on a 5.0 kg block. There is friction between the block and the floor and the block remains stationary. The coefficient of friction between the floor and block is mu = 0.80. What is the magnitude of the frictional force acting on the block? OA) 34.7 N B) 43.3 N C) 52.0 N D) 60.7 N 5.0 kg E) 69.3 N