Question

A person is pushing a sled along a horizontal surface. They exert a force of 200 N on the 75 kg sled. In addition a frictional force of 20 N acts on the sled.

What is the rate of acceleration of the sled? (in m s⁻² to 2.s.f)

Answer 1

Solution.

$F=200N;$

$m=75kg;$

$F_f=20N;$

$a-?;$

$\overrightarrow{ma}=\overrightarrow{F}+\overrightarrow{F_f};$

$ma=F-F_f\implies a=\dfrac{F-F_f}{m};$

$a=\dfrac{200N-20N}{75kg}=2.40ms^{-2};$

Answer: $a=2.40ms^{-2}.$