Answer: The elevator must be accelerating.
Explanation:
As the tension force is opposing to the the force of gravity on the load which is hung vertically, and the tension force can adopt any value in order to comply with Newton's 2nd law, if the tension force is less than the force due to gravity, this means that all system is not in equilibrium, so it must be accelerating.
If we assume that the downward is the positive direction, we can write:
mg - T = ma
If T = 0.9 mg, ⇒ mg (1-0.9) =0.1 mg = m a ⇒a = 0.1 g , in downward direction.
Answer:
799.54 ft
Explanation:
Linear thermal expansion is:
ΔL = α L₀ ΔT
where ΔL is the change in length,
α is the linear thermal expansion coefficient,
L₀ is the original length,
and ΔT is the change in temperature.
Given:
α = 1.2×10⁻⁵ / °C
L₀ = 800 ft
ΔT = -17°C − 31°C = -48°C
Find: ΔL
ΔL = (1.2×10⁻⁵ / °C) (800 ft) (-48°C)
ΔL = -0.4608
Rounded to two significant figures, the change in length is -0.46 ft.
Therefore, the final length is approximately 800 ft − 0.46 ft = 799.54 ft.
Energy stored in a capacitor is Electric Potential Energy. Capacitor is device used for storing energy. The work done to charge is a capacitor is stored in it in the form of Electrical potential energy. Electrical potential energy is defined as capacity to do work due to the position change. For example, we know fans have capacitor installed in it. When we turn off the fan, it continue moving using the electrical energy stored in the capacitor.
Answer:
The angular velocity of the propeller is 2.22 rad/s.
Explanation:
The angular velocity (ω) of the propeller is:
Where:
θ: is the angular displacement = 10.6 revolutions
t: is the time = 30 s
Therefore, the angular velocity of the propeller is 2.22 rad/s.
I hope it helps you!
