Answer:
Force of gravity, F = 0.74 N
Mass of an object, m = 1.2 kg
Distance above earth's surface, 
Mass of Earth, 
Radius of Earth, 
We need to find the force of gravity above the surface of Earth. It is given by :

R = r + d
R = 25370000 m

F = 0.74 N
So, the force of gravity on the object is 0.74 N. Hence, this is the required solution.
Answer:
Alaska: Hydrokinetic Energy Campbell CR9000X used for in-stream hydrokinetic device evaluation. Marine hydrokinetic energy power generation is an emerging sector in the renewable energy portfolio. Hydrokinetic devices convert the energy of waves, tidal currents, ocean currents or river currents into electrical power.
Answer:
Polished surfaces reduce heat loss
Answer : The weight of the car is 9800 N
Explanation :
It is given that,
The mass of the car, m = 1000 kg
We have to find the weight of the car. The weight of an object is defined as the force acting on it under the action of gravity. The mass of an object is the amount of matter present in it.
Using second law of motion :
W = m g
Where
m is the mass of the car
g is the acceleration due to gravity g = 9.8 N/kg
W = 1000 kg × 9.8 N/kg
W = 9800 N
So, the weight of the car is 9800 N.
Hence, this is the required solution.
Answer:
Explanation:
According to the Stefan-Boltzmann law for real radiating bodies:
(1)
Where:
is the energy radiated (in Watts)
is the Stefan-Boltzmann's constant.
is the Surface area of the body
is the effective temperature of the body (its surface absolute temperature) in Kelvin
is the body's emissivity
On the other hand, we are told the human body is roughly approximated to a cylinder of length
and circumference
.
The circumference of a circle is:
where
is the radius. Hence
.
Now we have to input this value for
in the Area of a cylinder formula:


(2)
Substituting (2) in (1):
(3)
Finally:
