An iceboat is at rest on a frictionless frozen lake when a sudden wind exerts a constant force of 200. N, towards the east, on the boat. Due to the angle of the sail, the wind causes the boat to slide in a straight line for a distance of 8.0 m in a direction 20 degrees north of east. What is the kinetic energy of the iceboat at the end of that 8.0 m?

K. E = 1600 J

Explanation:

The force exerted on boat is 200 N, which gives the acceleration to it = 200/m

here m is the mass of the boat.

The velocity after covering a distance of 8 m with this acceleration van be found by the relation

v² - u² = 2 a s

here u is the initial velocity, which is zero in this case because boat is at rest.

The v² = 2 x 200/m x 8

The K. E = 1/2 m v² = 1/2 m x 2 x 200/m x 8 = 1600 J