A contestant in a winter games event pushes a 45.0 kg block of ice across a froz

Question

A contestant in a winter games event pushes a 45.0 kg block of ice across a frozen lake as shown in the figure below. The coefficient of static friction is 0.1 and the coefficient of kinetic friction is 0.03. (Assume = 32°.)

(a) Calculate the minimum force F he must exert to get the block moving.
55.468 N

(b) What is its acceleration once it starts to move, if that force is maintained?

0.686 Wrong

I need help with part B, i am using the formula that was given to me in class but it says that it is incorrect

Explanation / Answer

b)

here

so the net force Fa accelerating the block is the total horizontal force minus the friction force

Fa = Fh - Ff
Fa = Fcos - (Fsin + mg)

as Fa = ma

ma = Fcos - (Fsin + mg)
a = Fcos - (Fsin + mg) / m

a = (55.468 * cos32deg - 0.03(55.468 * sin32deg + 45 * (9.81)) / 45
a = 0.7317 m/s²

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