Please help quickly Question 7
A boy uses a simple pulley to pull
10 m.
block up a ramp. The height of the ramp is 4 m and the length of the ramp is
Assuming that the ramp is frictionless, what is the ideal mechanical advantage of the ramp and does the pulley
provide any additional advantage?
A
The ideal mechanical advantage of the ramp is 0.4, and the pulley makes it easier to pull the
block up the ramp.
B
The mechanical advantage of the ramp is 2.5, and the pulley does not provide any additional
mechanical advantage.
с
The mechanical advantage of the ramp is 10, and the pulley does not provide any additional
mechanical advantage.
D
The mechanical advantage of the ramp is 40, and the pulley does provide an additional
mechanical advantage.

Suppose water is leaking from a tank through a circular hole of area ah at its bottom. when water leaks through a hole, friction and contraction of the stream near the hole reduce the volume of water leaving the tank per second to cah 2gh , where c (0 < c < 1) is an empirical constant. a tank in the form of a right-circular cone standing on end, vertex down, is leaking water through a circular hole in its bottom. (assume the removed apex of the cone is of negligible height and volume.) (a) suppose the tank is 20 feet high and has radius 8 feet and the circular hole has radius 2 inches. the differential equation governing the height h in feet of water leaking from a tank after t seconds is dh dt = − 5 6h3/2 . if the height of the water is initially 8 feet, how long will it take the tank to empty? (round your answer to two decimal places.)

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