Answer:
310.5 J
Explanation:
The total work done by Martha is equal to the increase in gravitational potential energy of the package, which is equal to
where
(mg) = 45 N is the weight of the package
is the increase in height of the package
The package is carried up 3 flights of stairs, each one with a height of 2.3 m, so the total increase in heigth is
And so, the work done by Martha is
Answer:
Machines are faster and more efficent
Explanation:
Answer:
Fa = 5000 [N]
Explanation:
To solve this problem we must use Newton's second law, which tells us that the sum of forces on a body is equal to the product of mass by acceleration.
Let's assume that the movement of the plane is to the right, any movement or force to the right will be marked with a positive sign, while any force or movement to the left, will be taken as negative.
The force of the turbine drives the plane to the right, therefore it is positive, the acceleration is constant and keeps the movement to the right, therefore it is positive, the wind drag force tries to prevent the movement of the plane to the left therefore it is negative, with this analysis we deduce the following equation.
ΣF = m*a
where:
ΣF = sum of forces [N] (units of Newtons)
m = mass = 65000 [kg]
a = acceleration = 3 [m/s²]
Fa = force exerted by the air [N]
200000 - Fa = 65000*3
Fa = 200000 - (3*65000)
Fa = 5000 [N]
Answer:
planting trees - increasing the amount of animal life on earth
Explanation:
from all the other options given, all except planting trees will increase global temperature.
1. deforestation: this removes vegetative cover and the amount of oxygen in the atmosphere.
2. increasing the use of gasoline burning vehicles: burning gasoline produces carbon dioxide which is a green house gas which traps heat in the atmosphere and causes global warming
3. increasing the industrial release of carbon dioxide: carbon dioxide is released when gasoline is burned in industries, this in-turn causes global warming.
Trees produces oxygen and sucks in carbon dioxide which causes global warming. more trees mean more oxygen and less carbon dioxide which translates to less global increase in temperature
The question is simply asking us to convert one unit, in this case temperature, to another unit. To do this, we need conversion factors to multiply, divide or relate to the original measurement. We do as follows:
Celsius = Kelvin - 273.15
310 - 273.15 = 36.85 degrees celsius
Fahrenheit = <span> (°</span>C<span> × </span>9<span>/5) + 32
</span> (36.85<span> × </span>9<span>/5) + 32 = 98.33 degrees fahrenheit
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Hope this helps.
