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.
To solve this exercise it is necessary to use the concepts related to Difference in Phase.
The Difference in phase is given by

Where
Horizontal distance between two points
Wavelength
From our values we have,


The horizontal distance between this two points would be given for

Therefore using the equation we have




Therefore the correct answer is C.
Answer
when there are ten they don't grow so well but when there is less than 10 they tend to grow
Answer:
176,000 N
Explanation:
Newton's second law:
∑F = ma
F = (4 × 40,000 kg) (1.1 m/s²)
F = 176,000 N
Answer:
When the starting and ending points are the same, the total work is zero.
Explanation:
option ( D )correct
A force is said to be conservative when the work done by the force in moving a particle from a point A to a point B is independent of the path followed between A and B and is the same for all the paths. The work done depends only on the particles initial and final positions. And when the initial and final position in conservative field are same the work done is said to be zero.