In: Physics
You are pulling a 4 kg object with 21 N at 60 degree with ground. What is acceleration?
Mass of object is 
Pulling force is 
Free body diagram is as shown

From the above diagram, resolve the pulling force into components.
i) horizontal component of force is
ii) vertical component of force is
Horizontal direction :
Apply newtons second law along horizontal direction,

Here
is the acceleration
in horizontal direction.
Substitute the known values,


Thus, the acceleration in horizontal direction is
Vertical Direction :
Weight of object is 
here
is acceleration due to
gravity and its value is
Thus, the weight of object is

Since
, there would not be any motion upwards. Thus its acceleration is
zero in upward direction.
Hence the acceleration of object is only due to horizontal
component and its value is