<span>Hydrogen
gas (H2) can be found in trace amounts in Earth’s atmosphere.
a. Hydrogen is found in acids.
b. Hydrogen gas is highly flammable.
c. Hydrogen reacts with oxygen to form water.
These are true, but they all describe chemical properties
of Hydrogen, not physical properties.
d. Hydrogen gas
is less dense than oxygen gas.
Yes ! This is a physical property of Hydrogen.
</span>
Answer:
<em>The crane lifts the crate up to 76 m high</em>
Explanation:
<u>Work Done by a Force</u>
The work done by a force of magnitude F that displaces an object by a distance y is given by

We know a crane does a work of 9,500 Joule to lift a crate and is using a force of 125 Nw.
The above equation can be solved to know the value of y in terms of the work and the force:

Plugging in the given values


The crane lifts the crate up to 76 m high
The turns ratio is equal to the voltage ratio. Let n1 and n2 be the primary and secondary turns. Then
5850V/120V=n1/n2
48.75=2680/n2
n2=2680/48.75
n2=55
Answer:
velocity of the metal cylinder = 0.343 m/s
Explanation:
Force putting the metal cylinder is given by
F = mv²/r
But this force will balance the frictional force between the metal cylinder and the turntable
The frictional force is given by
μN = μ × mg = 0.08 × 0.2 × 9.81 = 0.15696 N
r = 0.15 m, m = 0.2 kg,
F = mv²/r = 0.2 v²/(0.15) = 1.3333 v²
1.3333 v² = 0.15696
v² = 0.117
v = 0.343 m/s