Question

一臺拖拉機耕地時功率是60kw，10min內勻速前進了以900m．求它在耕地時受到的阻力．

Answer 1

拖拉機的速度V=

S

t

=

900m

10×60s

=1.5m/s；
阻力等于牽引力f=F=

P

V

=

60000W

1.5m/s

=4×10⁴N．
答：它在耕地時受到的阻力為4×10⁴N．