When you climb, earth exerts gravitational force on pack in downward direction(pointing towards the center of earth).
In order to climb, you need to work against work done by gravity on the pack.
Hence work done by you = work done by gravity on pack
= Force x displacement = 70 x 30 = 2100 J.
So you need to do 2100 joules of work to lift your pack.
Power is the rate of work done.
Therefore power = work done by you/time(in seconds)
= 2100/600 =3.5 watts
To solve this problem we will apply the concepts related to pressure, depending on the product between the density of the fluid, the gravity and the depth / height at which it is located.
For mercury, density, gravity and height are defined as
For the air the defined properties would be
We have for equilibrium that
Replacing,
Rearranging to find 
Therefore the elevation of the mountain top is 9400ft
Answer:
4.
a) W = 750 J
b) W = 2250 J
c) t = 2 sec
5. Answered in explanation
Explanation:
4.
The formula of power is given as:
P = W/t
where,
P = Power
W = Work Done
t = Time Taken
a)
Here,
P = 750 W
t = 1 sec
W = ?
Therefore,
750 W = W/1 sec
<u>W = 750 J</u>
b)
Here,
P = 750 W
t = 3 sec
W = ?
Therefore,
750 W = W/3 sec
W = (750 W)(3 sec)
<u>W = 2250 J</u>
c)
Here,
P = 750 W
t = ?
W = 1500 J
Therefore,
750 W = 1500 J/t
t = 1500 J/750 W
<u>t = 2 sec</u>
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5.
According to Kinetic Particle Theory, the molecules are tightly packed with each other, by strong inter-molecular forces and they can only vibrate at their position. While, molecules or particles in liquids have lesser attractive forces among them. They can move in layers and can take the shape of any container. <u>This is the reason why solid has a definite shape and liquid has none.</u>
Answer: Wallahi i don't know
Explanation:because i don't really care
The gravitational attraction between two planets is 4905.95 N
<h3>What is gravitational attraction?</h3>
When two objects with masses are placed at a distance, there will an attractive force acting between them.
According to the Newton's law of gravitation, gravitational force is
F = Gm₁m₂ /r²
where r is the distance between the masses m₁ and m₂ and G is the gravitational constant G = 6.67 x 10⁻¹¹ N-m²/kg²
Substitute the values into the expression, we get
F = 6.67 x 10⁻¹¹ x 2.25 x 10²⁰ x 6.20 x 10¹⁸ / (435,500 x 1000)²
F= 4905.95 N
Thus, the gravitational attraction between two planets is 4905.95 N.
Learn more about gravitational attraction.
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