You'll hear that force called different things in different places. It
may be called "electromotive force", "EMF", "potential difference",
or "voltage".

It's just a matter of somehow causing the two ends of the wire
to have different electrical potential. When that happens, the
free electrons in the copper suddenly have a burning desire to
travel ... away from the end that's more negative, toward the end
that's more positive, and THAT's an "electric current".

7 0

4 years ago

Oil of specific gravity 0.75 flows through a smooth contraction in a pipe at a volumetric flow rate of 3.2 cu ft / sec.Find the

pogonyaev

Answer:

The force required to hold the contraction in place is 665.91 N ↑

Explanation:

Given;

specific gravity of oil, γ = 0.75

Volumetric flow rate, V 3.2 Ft³/s = 0.0906 m³/s

$\gamma =\frac{\rho_o}{\rho_w}$

where;

$\rho_o$ is the density of oil

$\rho_w$ is the density of water = 1000 kg/m³

∴density of oil ( $\rho_o$ ) = γ × density of water( $\rho_w$ )

= 0.75 × 1000 kg/m³

= 750kg/m³

Buoyant Force = ρVg

= 750 × 0.0906 × 9.8

= 665.91 N ↑

This force acts upward or opposite gravitational force.

Therefore, the force required to hold the contraction in place is 665.91 N ↑

6 0

3 years ago

The difference in heights of the liquid in the two sides of the manometer is 43.4 cm when the atmospheric pressure is 755 mm hg.

Schach [20]

The atmospheric P is greater than the P in the flask, since the Hg level is lacking down lower on the side open to the atmosphere.

43.4 cm x (10 mm / 1 cm) = 435 mm

the density of Hg is 13.6 / 0.791 = 17.2 times better than the liquid in the manometer. This means that 1 mmHg = 17.2 mm of manometer liquid.

435 mm manometer liquid x (1 mm Hg / 17.2 mm manometer liquid) = 25.3 mm Hg

The pressure in the flask is 755 - 25.3 = 729.7 mmHg.

729.7 mmHg x (1 atm / 760 mmHg ) = 0.960 atm.

4 0

3 years ago