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A block of mass 5.0 kg is released from rest at the top of a ramp. The ramp has a height of 90 cm and is at an angle of 30 degrees with respect to the horizontal. When the block reaches the bottom, it has a speed of 2.7 m/s. How much energy was lost from friction

User Noir
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1 Answer

3 votes

Answer:

Energy lost to friction is 3847.5 joules

Step-by-step explanation:

Initial energy = Mgh

Initial energy= 5000*9.81*(90/100)

Initial energy = 44145 joules.

Final energy is kinectic plus mechanical energy.

Kinectic = 1/2 * m* v²

Kinectic = 1/2 * 5000* 2.7²

Kinetic energy = 18225 joules.

Mechanical energy= mghsin(tita)

Mechanical energy = 44145*sin30

Mechanical energy= 22072.5

Final energy is kinectic plus mechanical energy.

= 18225+ 22072.5

= 40297.5 joules.

Energy lost to friction is initial- final

=44145 joules- 402957.5

= 3847.5 joules

User Benoit Steiner
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