Answer:
5.886 J
Explanation:
Given:
The mass of the book is, 
kg
Height of lift is, 
m
Acceleration due to gravity is, 
m/s²
Now, gain in gravitational potential energy is a function of change in position and is given as:
Here, 
is the change in gravitational potential energy.
Plug in 0.5 kg for 
, 9.81 for 
and 1.2 for 
. Solve for
Therefore, the gain in gravitational energy of the book is 5.886 J.
The power that heat pump draws when running will be 6.55 kj/kg
A heat pump is a device that uses the refrigeration cycle to transfer thermal energy from the outside to heat a building (or a portion of a structure).
Given a heat pump used to heat a house runs about one-third of the time. The house is losing heat at an average rate of 22,000 kJ/h and if the COP of the heat pump is 2.8
We have to determine the power the heat pump draws when running.
To solve this question we have to assume that the heat pump is at steady state
Let,
Q₁ = 22000 kj/kg
COP = 2.8
Since heat pump used to heat a house runs about one-third of the time.
So,
Q₁ = 3(22000) = 66000 kj/kg
We known the formula for cop of heat pump which is as follow:
COP = Q₁/ω
2.8 = 66000 / ω
ω = 66000 / 2.8
ω = 6.66 kj/kg
Hence the power that heat pump draws when running will be 6.55 kj/kg
Learn more about heat pump here :
brainly.com/question/1042914
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Vi = 0m/s
A = 99m/
Vf = 445m/s
T = 4.5s
D = ?
D = Vi(t) + 1/2(a)(t²)
D = 0m/s ( 4.5s) + 1/2(99m/s²)(4.5s)²
D = 1002 m
D = 1 x 10³ m
Answer:
The speed of the light signal as viewed from the observer is c.
Explanation:
Recall the basic postulate of the theory of relativity that the speed of light is the same in ALL inertial frames. Based on this, the speed of light is independent of the motion of the observer.
