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 by mimiwhatsup: B) Velocity is a vector and requires a direction to completely describe it.
Velocity is the speed and direction of an object in motion.
Answer:
I think
D : Hydrogen gas has two atom , and oxygen has one atom
The steps in the heating of a metal seat in a park are:
Step 1: Heat travels from the sun to Earth
Step 2: Heat travels through atmosphere to the top of the seat
Step 3: Heat from the top of the seat travels through the seat to the lower parts of the seat.
-- Heat is transferred by radiation in Step 1 and Step 2. <em>(B)</em>
-- From the top of the seat to the bottom, heat is transferred by conduction.
There's no convection happening anywhere in the park-hot-seat scenario.