Help physics homework!!!?

Question

How much power must be expended by the carabao in plowing a clay loam soil-field at a rate of 15 meters/ minute? The furrow depth and width of cut by the plow is 10.5 cm and 16 cm, respectively. Neglect the weight of the plow and assume soil resistance of 29.4 N per cm2.

Answer 1

power=work done/time which is in seconds.

work done=force * distance.

power=29.4*pi 10.5^2 * 16/(15/60)

Answer 2

The area of the furrow cut is 10.5 cm by 16 cm = 168 cm².

The resistance is 29.4 N / cm², so the net force on the plow is 4900 N.

The work done per minute is ( 4900 N ) ( 15 m ) = 73,500 N.

The power is thus ( 73,500 N ) / ( 60 s ) = 1200 W.