A body of mass m accelerates uniformly from rest to \[{{v}_{1}}\] in time \[{{t}_{1}}\]. As a function of time t, the instantaneous power delivered to the body is [AIEEE 2004]

• A.             \[\frac{m{{v}_{1}}t}{{{t}_{1}}}\] 
• B.             \[\frac{mv_{1}^{2}t}{{{t}_{1}}}\]
• C.                         \[\frac{m{{v}_{1}}{{t}^{2}}}{{{t}_{1}}}\]          
• D.                           \[\frac{mv_{1}^{2}t}{t_{1}^{2}}\]