As you learned in the previous post, rock music relies heavily on chords. At the same time it is strongly influenced by the blues, especially in its early times during the 50s and 60s.
From blues to rock piano
The following example moves from the I to the IV to the V chord in the key of Bb. These are the same three chords which make up a blues. All of them are major chords, with Bb major played in root position and Eb and F played as inversions. The left hand simply plays the roots Bb, Eb and F plus a C to approach the next bar.
Add in a drum track and you have a rock sound already!
Eb major, 2nd inversion
F major, 1st inversion
Example 2 expands upon this idea by adding more rhythm to the piano part. The right hand plays eighth notes with a quick change between the I and IV chords. The alternating between the right and left hand creates even more movement and drives the music forward. The walk up at the end of bar 2 is simply an arpeggiated F major chord.
Piano with drums:
Check out the next post to playing slash chords in rock.