Q:What velocity does the boy attain if he throws the bricks one at a time?
Answer:Linear velocity since it moves back and firth and does not rotate like angular velocity.
Answer:
Following are the description on the chain surveying:
Explanation:
The checking which is also called a beginning of the test is indeed a line uniting the summit of a triangular with other fixed locations from both sides of a triangle. To verify the overall precision of a framework, the check-line is measured. When assessed mostly on the ground, every length of an examination line should match its height. It also is called a proof line that connects the top of the triangle with any fixed location in the contrary direction. It is utilized for verifying the preciseness of a work.
Answer:
(b)False
Explanation:
defined as
=
Where x is the distance from centroidal x-axis
y is the distance from centroidal y-axis
dA is the elemental area.
The product of x and y can be positive or negative ,so the value of
can be positive as well as negative .
So from the above expressions we can say that the product of
is different from
.
Answer:
Explanation:
Cop of reversible refrigerator = TL / ( TH - TL)
TL = low temperature of freezer = 20 °F
TH = temperature of air around = 75 °F
Heat removal rate QL = 75 Btu/min
W actual, power input = 0.7 hp
conversion on F to kelvin = (T (°F) + 460 ) × 5 / 9
COP ( coefficient of performance) reversible = (20 + 460) × 5/9 / (5/9 ( ( 75 +460) - (20 + 460) ))
COP reversible = 480 / 55 = 8.73
irreversibility expression, I = W actual - W rev
COP r = QL / Wrev
W rev = QL / COP r where 75 Btu/min = 1.76856651 hp where W actual = 0.70 hp
a) W rev = 1.76856651 hp / 8.73 = 0.20258 hp is reversible power
I = W actual - W rev
b) I = 0.7 hp - 0.20258 hp = 0.4974 hp
c) the second-law efficiency of this freezer = W rev / W actual = 0.20258 hp / 0.7 hp = 0.2894 × 100 = 28.94 %