Respuesta :
Answer:
0.06 A
Explanation:
We have given mass =0.954 kg
velocity =1.27 m/sec
efficiency =0.361 the output kinetic energy of the motor [tex]KE=\frac{1}{2}mv^2=\frac{1}{2}\times 0.954\times 1.27^2=0.769\ J[/tex]
Efficiency =0.361
so input to the motor = output/efficiency
so input to the motor = [tex]\frac{0.769}{0.361}=2.1301[/tex]
we know that [tex]P=\frac{E}{T}[/tex] where E is energy and T is time so [tex]P=\frac{2.1301}{7.88}=0.2703W[/tex]
We know that power P=VI we have given V=4.5 VOLT
So current [tex]I=\frac{P}{V}=\frac{0.2703}{4.5}=0.06 A[/tex]
Answer:
0.06 A
Explanation:
Given:
Mass of the toy car, m = 0.954 kg
Total potential provided, V = 4.50 volts
Efficiency of the toy, η = 36.1 % = 0.361
Time, t = 7.88 seconds
Initial speed of the toy car, v = 1.27 m/s
Now, the energy being released by the car while running is the kinetic energy
thus,
E = (1/2)mv²
on substituting the values, we get
E = (1/2) × 0.954 × 1.27²
or
E = 0.769 J
also,
Energy = Power × time
or
Power = Energy/time
on substituting the values, we get
Power = 0.769/7.88 = 0.0976 W
now,
the efficiency is given as;
η = (output power) / (Input power)
Input power = Voltage × current (I)
or
Input power = 4.50 × I
thus,
0.361 = 0.0976/(4.5 × I)
or
I = 0.060 A
