Answer:
Mass of the pull is 77 kg
Explanation:
Here we have for
Since the rope moves along with pulley, we have
For the first block we have
T₁ - m₁g = -m₁a = -m₁g/4
T₁ = 3/4(m₁g) = 323.4 N
Similarly, as the acceleration of the second block is the same as the first block but in opposite direction, we have
T₂ - m₂g = m₂a = m₂g/4
T₂ = 5/4(m₂g) = 134.75 N
T₂r - T₁r = I·∝ = 0.5·M·r²(-α/r)
∴ 
Mass of the pull = 77 kg.
Sound travels fastest through matter in the <em>solid state</em>.
I know this from having answered a huge number of Brainly questions that required me to look up things like this:
-- Speed of sound in air . . . about 340 m/s
-- Speed of sound in sea-water . . . about 1,500 m/s
-- Speed of sound in steel . . . about 5,960 m/s
The old style (incandescent) light bulb converts more energy
into heat than it does into light. If you're using it mainly as a
source of light, then it's a bummer, and its efficiency is very low.
BUT ... if you're using an incandescent light bulb as a heater, then
its efficiency is much better. It all depends on your point of view.
