Answer:
50 N
Explanation:
Efficiency of a machine can't be more than 1, so I assume you mean 40%. (Remember, efficiency and mechanical advantage are not the same).
Efficiency is the ratio of work out of a system to the work in to the system.
e = Wout / Win
Work is force times distance, so:
e = (Fout × Dout) / (Fin × Din)
Rearranging:
Fin = (Fout × Dout) / (e × Din)
Fin = (Fout / e) × (Dout / Din)
Fin = (Fout / e) / (Din / Dout)
We know that e = 0.40, and Fout = 120 N. Since there are 6 pulleys, we also know that Din/Dout = 6.
F = (120 N / 0.4) / 6
F = 50 N
Answer:
Explanation:
Newton's 2 nd law of motion tells that when equal torque is applied on object having higher moment of inertia , it will rotate slower .
Moment of inertia of boiled egg is higher because the whole egg rotates as s solid unit . Hence it will rotate slower or it rolls slower on an inclined surface .
In this way by applying Newton's law , we can identify raw or boiled egg .
The work performed on an object is the force multiplied by the distance it is moved, provided the movement is parallel to the force. Since that is the case here, we can get the work by W=Fd=1900N x 0.23m = 437J. This energy is used to split the wood.
Answer:

Explanation:
Height of the cliff is given as

now the time taken by the diver to hit the surface is given as



Now in the same time it has to cover a distance of 13.39 m
so the speed in horizontal direction is given as


