Answer:
positive
Explanation:
The ball is rolling down with a negative velocity, but the velocity is slowing down. therefore the velocity must increase in order for the ball to slow down.
For example let the ball's initial velocity be -15 m/s. and it is slowing down to let's say -13 m/s. Well this means that it's velocity has increase by 2 m/s. So, its acceleration is positive.
Answer:
F₁ = 4 F₀
Explanation:
The force applied on the string by the ball attached to it, while in circular motion will be equal to the centripetal force. Therefore, at time t₀, the force on ball F₀ is given as:
F₀ = mv₀²/r --------------- equation (1)
where,
F₀ = Force on string at t₀
m = mass of ball
v₀ = speed of ball at t₀
r = radius of circular path
Now, at time t₁:
v₁ = 2v₀
F₁ = mv₁²/r
F₁ = m(2v₀)²/r
F₁ = 4 mv₀²/r
using equation (1):
<u>F₁ = 4 F₀</u>
Answer:
The speed of the riders on the Singapore Flyer is approximately 0.262 m/s
Explanation:
The dimensions of the tallest Ferris wheel in the world are;
The diameter of the Ferris wheel, D = 150 m
The tine it takes the Ferris wheel to make a full circle, T = 30 minutes = 30 min × 60 s/min = 1,800 seconds
The angular velocity of the Ferris wheel, ω = 2·π/T
The linear velocity of the Ferris wheel, v = r·ω = The speed of the riders
Where;
r = The radius of the Ferris wheel = D/2
D = 150 m
∴ r = 150 m/2 = 75 m
∴ v = r·2·π/T
∴ v = 75 m × 2 × π/(1,800 s) ≈ 0.262 m/s
The speed of the riders on the Singapore Flyer, v ≈ 0.262 m/s
The thermosphere is a layer of Earth's atmosphere. The thermosphere is directly above the mesosphere and below the exosphere. It extends from about 90 km (56 miles) to between 500 and 1,000 km (311 to 621 miles) above our planet.
Answer:
- Energy from sun travels to the earth by radiation of waves.
- Energy is the capacity to do the work whereas power is the rate of doing work or the rate of energy transfer.
- Energy always transforms from higher grade to a lower grade.
Positive feedback are not good when it disturbs the stability too much over a wide range.
No, negative feedback are not always bad because they enhance the stability of our system, resist the change in a system making it consistent and have a narrower range of variation.
Explanation:
The energy from the sun travels a huge distance in vacuum and atmosphere.
- The solar energy travels to the earth in the form of electromagnetic radiations which do not require any medium of transmission and are capable of travelling in vacuum by the mode called radiation. In this mode the packets of energy get directly transmitted from the source to its surroundings. This packet of energy is called quanta.
- Energy is the capacity to do work. Everything that we see and feel around us is some sort of energy. Every matter is the condensed form of energy the other forms that we cannot touch or feel is the wave form of energy. The wave form of energy stays in two form either stored in a mass or it is in transition. Now the concept of power arises form the energy in motion, power is defined as the rate of doing work or the rate of energy transfer. We usually use the term power for the energy in motion.
- We can burn a gallon of fuel only once because it undergoes a chemical change and the chemical changes are mostly permanent in nature. There is a certain direction to which the energy can flow spontaneously. When we burn the fuel then the stored chemical energy of the fuel gets converted into heat and light and the heat energy released during the combustion of the fuel is sufficient to further provide the heat of combustion of fuel.
- Energy always transforms from high grade to the lower grade and the converse is not possible spontaneously.
Positive feedback are not good when it disturbs the stability too much over a wide range.
No, negative feedback are not always bad because they enhance the stability of our system, resist the change in a system making it consistent and have a narrower range of variation.
