Question

find the magnitude of the net force on a 20kg mass if it accelerates uniformly from 5.8 m per second in 3 seconds

Answer 1

Given conditions ⇒

Mass of the body = 20 kg.
Final Velocity = 5.8 m/s.
Initial velocity = 0
Time = 3 seconds. 

Using the Formula, 

 Acceleration = (v - u)/ t
 = (5.8 - 0)/ 3
 = 1.6 m /s².

Now, Using the Formula, 

Force = mass × acceleration
 = 20 × 1.6
 = $\boxed{32 N}$


Hence, the magnitude of net force acting on the body is 32 N.


Hope it helps . :-)

Answer 2

We know that a=(v-u)/t
Where a is acceleration
u is initial velocity and v is final velocity
t is the time

a=(5.8-0)/3      (Considering object initially at rest)
a=5.8/3
a=1.933 m/s²

We also know that
F=ma
where 
F is the force,
m is mass and a is the acceleration
F=20 × 1.933
F=38.66 N
So, the magnitude of force will be 38.66N