Adockworker applies a constant horizontal force of 73.0 n to a block of ice on a smooth horizontal floor. the frictional force is negligible. the block starts from rest and moves a distance 13.0 m in a time 4.50 s.(a)what is the mass of the block of i found this to be 56.9kg and got it right.(b)if the worker stops pushing at the end of 4.50 s, how far does the block move in the next 4.20s ?

(a) Mass of the car will be 56.8285 kg

(b) Distance traveled in next 4.20 sec will be 33.9619 m

Explanation:

We have given horizontal force F = 73 N

As it is given that the block starts from the rest so initial velocity u = 0 m/sec

Distance traveled s = 13 m

Time t = 4.5 sec

(a) From second equation of motion

Now according to newton second law force F = ma

So mass

(b) Velocity after 4.20 sec v = u+at

v=0+1.2839×4.20 = 5.39 m/sec

So initial velocity for second case = 5.39 m/sec

From second equation of motion

they start with the same