The thermal efficiency of an engine is
where
W is the work done by the engine
Q is the heat absorbed by the engine to do the work
In this problem, the work done by the engine is W=200 J, while the heat exhausted is Q=600 J, so the efficiency of the machine is
The relationship between resistance R and resistivity
is
(1)
where L is the length of the wire and A is the cross-sectional area.
In our problem, the radius of the wire is half the diameter: r=1 mm=0.001 m, so the cross-sectional area is
The length of the wire is L=20 m and the resistance is
.
By re-arranging equation (1), we can find the resistivity of the wire:
Answer:
Pressure
Explanation:
The measure of how much force is applied to an object from gas particle bouncing into it is called pressure.
Pressure is defined as the force per unit area on a body.
Mathematically;
Pressure =
The pressure of a gas is the combined force with which gas molecules bombard a unit area of the wall of the container. It is the sum of all tiny pushes on the wall of the container.
Various units of pressure are atm, mmHg, torr, pascal e.t.c
Answer:
Explanation:
1 ha = 10⁴ m²
1375 ha = 1375 x 10⁴ m² = 13.75 x 10⁶ m²
In flow in a month = .5 x 10⁶ x 30 m³ = 15 x 10⁶ m³
Net inflow after all loss = 18.5 - 9.5 - 2.5 cm = 6.5 cm = .065 m
Net inflow in volume = 13.75 x 10⁶ x .065 m³= .89375 x 10⁶ m³
Let Q be the withdrawal in m³
Q - 15 x 10⁶ - .89375 x 10⁶ = 13.75 x 10⁶ x .75 = 10.3125 x 10⁶
Q = 26.20 x 10⁶ m³
rate of withdrawal per second
= 26.20 x 10⁶ / 30 x 24 x 60 x 60
= 26.20 x 10⁶ / 2.592 x 10⁶
= 10.11 m³ / s