# physics

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In the Figure the pulley has negligible mass, and both it and the inclined plane are frictionless. Block A has a mass of 1.3 kg, block B has a mass of 2.7 kg, and angle è is 26 °. If the blocks are released from rest with the connecting cord taut, what is their total kinetic energy when block B has fallen 27 cm? and in ths figure block b is hanging down and block A is on inclined.

• physics - ,

The increased (and total) kinetic energy equals the lost potential emergy. If block B has fallen 0.27 m vertically, block A has moved up the incline for an altitude change of 0.27 sin 26 = 0.1184 m

Total P.E. lost = 2.7*9.8*0.27 - 1.3*9.8*0.1184 = 7.14 - 1.51 J = 5.63 J
That equals the total K.E. increase,
(1/2)(MA + MB)*V^2

• physics - ,

thank u so much for help Drwls!!!!!!!!!!1

• physics - ,

The increased (and total) kinetic energy equals the lost potential emergy. If block B has fallen 0.27 m vertically, block A has moved up the incline for an altitude change of 0.27 sin 26 = 0.1184 m

Total P.E. lost = 2.7*9.8*0.27 - 1.3*9.8*0.1184 = 7.14 - 1.51 J = 5.63 J
That equals the total K.E. increase,
(1/2)(MA + MB)*V^2