From the word compound, the compound machine is already a combination of two or more types of simple machine. Thus, the answer is letter C. Because of its complexity, it is able to perform several other functions than a simple one.
Answer:
1.28 x 10^4 N
Explanation:
m = 1500 kg, h = 450 km, radius of earth, R = 6400 km
Let the acceleration due to gravity at this height is g'
g' / g = {R / (R + h)}^2
g' / g = {6400 / (6850)}^2
g' = 8.55 m/s^2
The force between the spacecraft and teh earth is teh weight of teh spacecraft
W = m x g' = 1500 x 8.55 = 1.28 x 10^4 N
Answer:
The rate of heat removed from inside the refrigerator is 300 watts.
Explanation:
By the First Law of Thermodynamics and the definition of a Refrigeration Cycle, we have the following formula to determine the rate of heat removed from inside the refrigerator (
), in watts:
(1)
Where:
- Rate of heat released to the room, in watts.
- Rate of electric energy needed by the refrigerator, in watts.
If we know that
and
, then the rate of heat removed from inside the refrigerator is:


The rate of heat removed from inside the refrigerator is 300 watts.
Answer:
a) According to Newton's law of gravitation, as the distance between the Moon and the Earth decreases, the gravitational attraction increases and vice versa
The gravitational force of the Moon on the Earth causes the Earth to be slightly bulged on the side directly facing the Moon
The gravitational force also pulls the water bodies on the Earth's surface towards the Moon in the same manner and the effect is more pronounced due to the ability of the liquid water to assume a shape based on the magnitude of the gravitational field attracting it
Therefore, the region where the Moon is closest to the Earth we have a high tide as the water level rises and the region which is perpendicular to where the Moon is located has a low tide
b) The two special types of tides are
1) The neap tide
2) The spring tide
Neap tide
Neap tide occurs when the Sun and Moon are 90° apart from each other when they are viewed by an observer from Earth
The gravitational pull of the Sun cancels (partially) the effect of the gravitational pull and tidal force of the Moon, resulting in minimum tidal range
Spring Tide
Spring tide occurs when the Earth, the Moon, and the Sun are simultaneously inline, such that the Sun reinforces the gravitational pull and tidal force of the Moon, resulting in a maximum tidal range
Explanation: