Block with of mass m is at rest on horizontal frictionless surface at time t=0. a force given by f=bt+c is applied horizontally to the center of gravity of the block. if m=4, b=c and c=0.5, what is the magnitude of block velocity at t=2 s?

Explanation:

From the second law of Newton movement laws, we have:

, and we know that a is the acceleration, which definition is:

, so:

The next step is separate variables and integrate (the limits are at this way because at t=0 the block was at rest (v=0):

(This is the indefinite integral), the definite one is:

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