Answer:
Work done in stretching the spring = 7.56 lb-ft.
Step-by-step explanation:
Normal length of the spring = 8 in or
ft
=
ft
If the spring has been stretched to 11 inch then the stretched length of the spring is = 11 in
=
ft
Force applied to stretch the spring = 12 lb
By Hook's law,
F = kx [where k is the spring constant and x = length by which the spring is stretched]
12 = k(
)
k = 18
Work done (W) to stretch the spring by
ft will be
W = 
= 
= ![18[\frac{x^{2}}{2}]^{\frac{11}{12}}_0](https://tex.z-dn.net/?f=18%5B%5Cfrac%7Bx%5E%7B2%7D%7D%7B2%7D%5D%5E%7B%5Cfrac%7B11%7D%7B12%7D%7D_0)
= 9(
)²
= 7.56 lb-ft
(a) He would drive 96 km in an hour because 1152 divided by 12 is 96
(b) He is technically on schedule because he is driving 104 km per hour, instead of 96, so if he keeps driving at the same rate, he should get there in under 12 hours
The answer is 3.4 because 30 can’t be divided equally into 9, reason being that 9 x 30 = 270 which doesn’t make sense, so you have to divide 30 equally into 9 parts then turn it into a ratio.
Answer: 43.3 square inches
Step-by-step explanation:
Formula for Triangle: A = bh/2
Key:
* = multiple
/ = divide
Fill in the formula with what you know:
A = bh/2
A = 5 * 4.33 / 2
A= 21.65 / 2 = 10.825 square inches
However, 10.825 is not our answer. 10.825 is the area of only one triangle. Since all four of the triangles are congruent (or the same) we can:
Add: 10.825 + 10.825 + 10.825 + 10.825 = 43.3 square inches
OR
Multiple: 10.825 * 4 = 43.3 square inches
Thus, the surface area of the pyramid is 43.3 square inches.