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.
Answer:




Explanation:
The electrical reactance is defined as:

Where:

So, replacing the data provided by the problem:

Now, the impedance can be calculated as:

Where:

Replacing the data:

In order to find the magnitude of the impedance we can use the next equation:

We can use Ohm's law to find the current:

Therefore the current is:

And its magnitude is:

Finally the phase angle of the current is given by:

Answer:
a sound wave is an electromagnetic wave
Answer:
3.71 m/s in the negative direction
Explanation:
From collisions in momentum, we can establish the formula required here which is;
m1•u1 + m2•v2 = m1•v1 + m2•v2
Now, we are given;
m1 = 1.5 kg
m2 = 14 kg
u1 = 11 m/s
v1 = -1 m/s (negative due to the negative direction it is approaching)
u2 = -5 m/s (negative due to the negative direction it is moving)
Thus;
(1.5 × 11) + (14 × -5) = (1.5 × -1) + (14 × v2)
This gives;
16.5 - 70 = -1.5 + 14v2
Rearranging, we have;
16.5 + 1.5 - 70 = 14v2
-52 = 14v2
v2 = - 52/14
v2 = 3.71 m/s in the negative direction