We can solve this problem by stating that the summation
of momentums must be zero. That is, the momentum at one end of the pivot must
be equal to the momentum at the other end.
Momentum 1 = Momentum 2
Since Momentum is the product of Force and Distance, and
with this rule created, we can say that:
F1 * d1 = F2 * d2
Where,
F1 = 60 lbs
d1 = 2 inches from the pivot
F2 = unknown X
d2 = 3 inches from the pivot
Substituting to the equation to find for F2:
60 lbs * 2 inches = F2 * 3 inches
F2 = 40 lbs
<span>Therefore 40 lbs of upward force must be pushed to open
the valve.</span>
<span>Answer: B</span>
If one is to choose among given choices and the order is not important, we use the concept of combination. First, we calculate for the sample space or number available since there is a total number of 12 electives and a student may choose 2 out of them.
S = 12C2
That is "the sample space is equal to combination of 12 taken 2". The answer to this is equal to 66.
Next, we determine the number of outcomes. The equation will be,
O = (5C1) x (3C1)
That is "outcome is equal to combination of 5 taken 1 times combination of 3 taken 1". This is equal to 15. The probability is equal to,
P = O/S
Substituting,
P = (15/66) = 0.227270
The answer to this item is the third choice.
Answer:Obtain a systematic sample by selecting every 20th vehicle that passes (in any lane and going in any direction).
Step-by-step explanation:
<span> He could draw a diagram of a rectangle with dimensions x – 1 and x – 6 and then show the area is equivalent to the sum of x2, –x, –6x, and 6.</span>