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:
The final velocity is 31.86 m/s.
Explanation:
The final velocity can be found using the following equation:

Where:
is the final velocity =?
is the initial velocity = 33.9 m/s
a is the acceleration = -2.02 m/s²
t is the time = 1.01 s

Therefore, the final velocity is 31.86 m/s.
I hope it helps you!
A hydraulic jack can be force multiplier because it can take a small force
Explanation:
a) d = ½.a.t²
200 = ½(4)t²
200 = 2t²
t² = 200/2
t² = 100
t =√100 = 10 s
b) Vt = a. t
= 4(10)
= 40 m/s
c) V av. = d/t = 200/10 = 20m/s
here since string is attached with a mass of 2 kg
so here tension force in the rope is given as

here we will have

now we will have speed of wave given as

here we will have


now we know that frequency is given as
F = 100 Hz
now wavelength is given as


so wavelength will be 0.16 m