Answer:
The sound intensity that the other student measure, I₂ is expected to be;
A) 6.2 × 10⁻⁸ W/m²
Explanation:
The measure of sound intensity is given by the following formula;


Where;
I = The intensity
R = The radius
P = The power of the sound
Whereby we have;
The distance of the two people talking, R₁ = 3.0 m
The measure of the sound intensity, I₁ = 1.1 × 10⁻⁷ W/m² (from an online source)
The distance of the other student from the two people talking, R₂ = 4.0 m
Therefore, the estimate of the sound intensity, I₂, is given as follows;


I₂ = 6.1875 × 10⁻⁸ W/m²
∴ The sound intensity that the other student measure, I₂ ≈ 6.2 × 10⁻⁸ W/m²
Answer:
The correct answer is B. Algae and fungi are biotic; temperature and rainfall are abiotic.. FURTHER EXPLANATION. An ecosystem consists of all living and non-living factors in an environment that interact and that are interdependent with each other.. All living things or factors in an ecosystem are called biotic factors.Examples include organisms like plants, animals, humans, etc.
Explanation:
Answer:
Explanation:
We shall write the velocities given in vector form to make the solution easy.
The velocity of water with respect to earth that is waV(e) makes 30 degree with north or 60 degree with east so in vector form
waV(e) = 2.2 cos 60 i + 2.2 sin 60 j
waV(e) = 1.1 i + 1.9 j
Similarly , velocity of wind with respect to earth that is wiV(e) , is making 50 degree with west or - ve of x axes so we cal write it in vector form as follows
wiV(e) = - 4.5 cos 50 i - 4.5 sin 50 j
wiV(e) = - 2.89 i - 3.45 j
Now we have to calculate velocity of wind with respect to water that is
wiVwa
wiV( wa) = wiV ( e)+ eV(wa)
= wiV( e)- waV(e)
- 2.89 i - 3.45 j - 1.1 i - 1.9 j
= - 3.99 i - 5.35 j
Magnitude of this relative velocity
D² = 3.99² + 5.35²
d = 6.67 m /s
Answer:
The average current I supplied to the cars motor is 0.225 Amperes.
Explanation:
The mass of the toy car is given as, m = 0.6 kg
The toy car operates at a steady speed of, v = 3.43 m/s.
It achieves the steady speed after a time, t = 5.69 seconds.
The total kinetic energy of the car is given by,
E = 
= 0.5 × 0.6 × 
= 3.53 Joules
Since the efficiency of the motor is 30.6% = 0.306
The electrical energy equivalent is supplied to motor =
.
The electrical energy is given by P × t = I × V × t = 11.54 Joules
P is the electric power where P = I × V where V is the voltage of the cell and is the average current, I.
Therefore we can write I × 9 × 5.69 = 11.54 Joules.
So the average current I =
= 0.225 Amperes.