Question

We want to look at several ways that we can find the kinetic energy of an object.  
One method is to find the velocity of the object, and then use K=1/2mv²  
Another method is to find the work done, which tells us by how much the kinetic energy has changed.

A ball of mass 2 kg starts from rest. Find its final K_f for each example.  
It is accelerated at 5 m/s² for 2 s.  
64 J  
100 J  
200 J  
50 J
25 J
10 J

Tries 0/2

It experiences a force of 8 N for 2 s.  
100 J  
64 J  
200 J  
50 J
25 J
16 J

Tries 0/2

It experiences a constant force of 30 N for 20 m.  
200 J  
600 J  
100 J  
50 J
25 J
10 J

Answer 1

Find acceleration in each case using this find final speed with the help of equations of motion.