A constant force acting on a body of mass 3.0 kg chages its speed from `2.0m s ^(-1) " to " 3.5ms^(-1)` in 25 s . The direction of motion of the body remains unchanged . What is the magnitude and direction of the force ?

Explanation

Mass of the body m , = 3.0 kg ,
Initial velocity of the body , u = `2.0ms^(-1)`
Final velocity of the body , v = `3.5ms^(-1)`
Time , t = 25 s
From Newton's second law of motion ,
`F=ma=(m(v-u))/(t)=(3.0(3.5-2.0))/(25)=0.18N`
`therefore` Magnitude of force acting on the body , F = 0.18 N . The direction of force acting on the bod is along the direction of motion of the body because force is positive .