Answer:
Explanation:
First, we need to solve for the power absorbed by the bulb.
Formula [ p = vi ]
p = 12 * 150 * 10^-3
p = +1.8W
Second, we can solve for the power aborbed in a interval of 20 minutes.
Formula [ e = vit ]
e = 12 * 150 * 10^-3 * 20 * 60
e = 2,160J
Just a note that "20 * 60" represents the time given in seconds.
Best of Luck!
Answer:


Explanation:
Given:
temperature of source reservoir, 
temperature of sink reservoir, 
energy absorbed from the source, 
work done, 
a.
<u>Now change in entropy of the surrounding:</u>

<em>Since heat engine is a device that absorbs heat from a high temperature reservoir and does some work giving out heat in the universe as the byproduct.</em>



b.
<u>We know Carnot efficiency is given as:</u>



<u>Now the Carnot work done:</u>


.......................(1)
c.
From eq. (1) we have the Carnot work, so the difference:



Now, we find:

Answer:
D. Forces between molecules
Explanation:
Specific heat capacity of water can be defined as the amount of heat a gram of water must lose or absorb in order to change its temperature by a degree Celsius. It is measured in Joules per kilogram per degree Celsius (J/kg°C). Generally, the specific heat capacity of water is 4.182J/kg°C and is the highest among liquids.
Mathematically, the specific heat capacity of a substance is given by the formula;

Where;
Q represents the heat capacity or quantity of heat.
m represents the mass of an object.
c represents the specific heat capacity of water.
dt represents the change in temperature.
Cohesion is a property of water and it typically refers to the attraction between molecules of water which holds them together.
In Science, the property which helps to explain differences in the specific heat capacities of two substances is the forces between molecules.
This ultimately implies that, the more closely bonded the atoms of a substance are, the higher or greater would be the substance's specific heat capacity. Thus, it varies for the various states of matter i.e solid, liquid and gas.
Answer:
D. The moon is closer to Earth than the sun.
Explanation:
Tides are formed as a consequence of the differentiation of gravity due to the moon across to the Earth sphere.
Since gravity variate with the distance:
(1)
Where m1 and m2 are the masses of the two objects that are interacting and r is the distance
For example, see the image below, point A is closer to the moon than point b and at the same time the center of mass of the Earth will feel more attracted to the moon than point B. Therefore, that creates a tidal bulge in point A and point B.
The Sun tidal force contributes to the tidal force of the moon over the earth making high tides higher and low tides lower.
However, even when the sun is more massive than the moon, it is farther away from the Earth than the moon. So, it is clear by equation 1 that the moon's gravity has a greater effect on Earth's oceans than the sun's gravity.
Answer:
14 cm
Explanation:
Power of eye = 57.1 D
The relation between the focal length and the power is
f = 1 / P = 1 / 57.1 = 0.0175 m = 1.75 cm
The distance between the image and the lens is, v = 2 cm
Let the distance between the object and the eye is u
Use the lens equation
1/ f = 1 / v - 1 / u
1 / 1.75 = 1 / 2 - 1 / u
1 / u = 1 / 2 - 1 / 1.75
1 / u = (1.75 - 2) / 3.5
u = - 14 cm
Thus, the distance between the feature and eye is 14 cm .