The ideal mechanical advantage of a slope is given by the ratio between the output load, which is simply the weight of the object (), and the input force applied to move the object along the slope:
The energy conservation law states that the potential energy of the object when it reaches the final height h is equal to the work done to move the object along the distance of the slope , i.e.
From this we find
Therefore, we can substitute this into the formula of the ideal mechanical advantage and calculate its value:
Please said thanks
Answer:
- boat speed: 17.25 mph
- current: 2.5 mph
Step-by-step explanation:
Upstream, the speed of the current (c) subtracts from the speed of the boat (b) to give the net speed. Downstream, the speed of the current adds. We can make use of the relation ...
speed = distance/time
b-c = 29.5/2 = 14.75 . . . . . miles/hour
b+c = 59.25/3 = 19.75 . . . .miles/hour
Subtracting the first equation from the second, we get ...
(b+c) -(b-c) = 19.75 -14.75
2c = 5
c = 2.5
Then either equation can be used to find b:
b = 14.75 +c = 17.25
The speed of the boat in still water is 17.25 miles per hour; the speed of the current is 2.5 miles per hour.
Answer:
aww this was the day before my birthday
8/4 should work, because the numerator's higher than the denominator.
The correct answer is A. 2.5 meters. One meter has approximately 3 feet, so it would make sense for a car to be about 7.5 feet in length
Hope this helps
