Answer:
The average speed of the elevator going down in the abandoned mine is 17.722mph.
Explanation:
If the elevator takes 90 seconds to descend a height of 713m, the average speed of the elevator is:
And if 1m/s is 2.23694mph, the average speed is:
.
Answer:
V₁ = √ (gy / 3)
Explanation:
For this exercise we will use the concepts of mechanical energy, for which we define energy n the initial point and the point of average height and / 2
Starting point
Em₀ = U₁ + U₂
Em₀ = m₁ g y₁ + m₂ g y₂
Let's place the reference system at the point where the mass m1 is
y₁ = 0
y₂ = y
Em₀ = m₂ g y = 2 m₁ g y
End point, at height yf = y / 2
= K₁ + U₁ + K₂ + U₂
= ½ m₁ v₁² + ½ m₂ v₂² + m₁ g 
+ m₂ g
Since the masses are joined by a rope, they must have the same speed
= ½ (m₁ + m₂) v₁² + (m₁ + m₂) g
= ½ (m₁ + 2m₁) v₁² + (m₁ + 2m₁) g
How energy is conserved
Em₀ =
2 m₁ g y = ½ (m₁ + 2m₁) v₁² + (m₁ + 2m₁) g
2 m₁ g y = ½ (3m₁) v₁² + (3m₁) g y / 2
3/2 v₁² = 2 g y -3/2 g y
3/2 v₁² = ½ g y
V₁ = √ (gy / 3)
Answer:
<em>Hewo Otaku Kun Here! (UwU)</em>
Explanation:
1. A rock sitting at the edge of a cliff has potential energy. If the rock falls, the potential energy will be converted to kinetic energy.
2. Tree branches high up in a tree have potential energy because they can fall to the ground.
3. A stick of dynamite has chemical potential energy that would be released when the activation energy from the fuse comes into contact with the chemicals.
4. The food we eat has chemical potential energy because as our body digests it, it provides us with energy for basic metabolism.
5. A stretched spring in a pinball machine has elastic potential energy and can move the steel ball when released.
6. When a crane swings a wrecking ball up to a certain height, it gains more potential energy and has the ability to crash through buildings.
7. A set of double "A" batteries in a remote control car possess chemical potential energy which can supply electricity to run the car.
<em>happy to help!</em>
<em>from: Otaku Kun ^^</em>
<h2>
Answer: 502.08 J</h2>
Explanation:
The heat (thermal energy) needed in to raise the temperature in a process can be found using the following equation:
(1)
Where:
is the heat
is the mass of the element (<u>water</u> in this case)
is the specific heat capacity of the material. In the case of water is 
is the variation in temperature <u>(which is increased in this case)</u>
Knowing this, let's rewrite (1) with these values:
(2)
Finally:
Answer:
0.33 s
Explanation:
For this case, as the object is hung on the end of an unstretched spring, we can consider this system as a simple pendulum.
For this system, we can determine the period of the motion using the following formula:
T = 2π√(L/g)
Where: T = period (in sec), L = lenght of the spring, g = acceleration of garvity = 9.8 m/s²
By the exact time the object is 2.75 cm before coming to rest, that will be the lenght of the spring we can consider (2.75 cm = 0.0275 m)
Finally:
T = 2π√(0.00275/9.8)
T = 0.33 sec
