Answer:
Rate at which current flows is measured in amperes
Explanation:
The rate of flow of electrons constitutes the current. The electrons flow from lower electric potential to higher electric potential. When there is no potential difference then no electron will flow. The direction of the current and the electron are in opposite direction.
The direction of electron from the negative terminal to the positive terminal. The direction of current is from the positive terminal to the negative terminal.The current is measured in ampere.
The expression for current and the charge is as;
Here, q is the charge, t is the time taken and I is the current.
According to the given problem, Jodi made a list about electric current to help her study for a test. He described that electrons move from areas of low to high electric potential, voltage causes current to flow and movement of electrons is continuous in a current.
But he did error. It should be "rate at which charges flow" instead of rate at which current flow.
Therefore, the option (4) is correct.
Answer:
357.6g
Explanation:
Given parameters:
Density = 12.459g/cm³
Volume of metal = 28.7cm³
Unknown:
Mass of metal = ?
Solution:
The density of a substance is its mass per unit volume.
To find the mass;
Mass of metal = density x volume
Now insert the parameters and solve;
Mass of metal = 12.459 x 28.7 = 357.6g
Given:
Gasoline pumping rate, R = 5.64 x 10⁻² kg/s
Density of gasoline, D = 735 kg/m³
Radius of fuel line, r = 3.43 x 10⁻³ m
Calculate the cross sectional area of the fuel line.
A = πr² = π(3.43 x 10⁻³ m)² = 3.6961 x 10⁻⁵ m²
Let v = speed of pumping the gasoline, m/s
Then the mass flow rate is
M = AvD = (3.6961 x 10⁻⁵ m²)*(v m/s)*(735 kg/m³) = 0.027166v kg/s
The gasoline pumping rate is given as 5.64 x 10⁻² kg/s, therefore
0.027166v = 0.0564
v = 2.076 m/s
Answer: 2.076 m/s
The gasoline moves through the fuel line at 2.076 m/s.
C. It transfer energy as heat to the surrounding air. This answer is incorrectly
Answer:
i) 0.9504
ii) 0.0452
Explanation:
Given data: reliability of hydraulic brakes= 0.96
reliability of mechanical brakes = 0.99
So the probability of stopping the truck = 0.96×0.99= 0.9504
At low speed
case: A works and B does not
= 0.96×(1-0.99) = 0.0096
case2 : B works and A does not
= 0.99×(1-0.96) = 0.0396
Therefore, probality of stopping = 0.0096+0.0396 = 0.0492
