A block of mass 2

:

The mass of the block, m = 2 kg

Force that is being applied, F = 20 N

Acceleration due to gravity, g = 10 m/s²

Time for which the force acts, t = 1 s

The applied force, F = mgsinθ + ma

20 = 2×10sin37° + 2×a

20 = 12 + 2a

⇒ a = 4 m/s²

The distance travelled by the block, s = 1/2 at²

= 0.5×4×1×1 = 2m

(a.) Maximum work done = Fs

= 20 × 2

= 40 J

(b.) If the work done by the applied force = 40 J

Distance travelled by the block = work done/ force applied

= 40/20 = 2m

Height corresponding to this distance, h = 2sin37° = 1.2 m

Work done by force of gravity = -mgh

= -2 × 10 × 1.2

= -24 J

(where the negative sign indicates the that displacement is against gravity)

(c.) Speed of the block after 1s = at = 4×1 = 4 m/s

Kinetic energy corresponding to this = 1/2 mv²

= 0.5 × 2 × 4 × 4

= 16 J