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Homework Statement
An adult is pulling two small children in a sleigh over level snow. The sleigh and children have a total mass of 47kg. The sleigh rope makes an angle of 23degrees with the horizontal. The coefficient of kinetic friction between the sleigh and the snow is 0.11. Calculate the magnitude of the tension in the rope needed to keep the sleigh moving at a constant velocity.
Homework Equations
Fk=μFn
Fg= mg
ƩFx=ma(x)
ƩFy=ma(y)
The Attempt at a Solution
Fn≠Fg
Fn= Fgcosθ
= mgcosθ
= (47kg)(9.8m/s^2)cos23
Fn= 424N
Fg=mg
=(47kg)(9.8m/s^2)
Fg=461N
Fk=μFn
= (0.11)(424N)
Fk=46.64N
If it is to move at a constant velocity, there would be no acceleration
ƩFx=ma(x)
Ft+ (-Fk)=ma(x)
Ft=ma(x)+Fk
but if there is no acceleration then a=0
Ft=Fk
But, that's not the case.
Ideas?