I would say A, although it depends on what kind of machine. If it does not recycle, then most likely C. I would be able to give more context based on what kind of machine it is.
Answer:
No
Explanation:
According to physics, the work done by porter is zero but in reality porter gets tired as muscular energy is being used up.
In physics, work is the dot product of force and displacement. when the porter moves with the luggage, the weight act downwards while the porter moves forward. The angle between force and displacement is 90°. Thus, work done by the porter is zero.
The muscles are doing work in this case which is not calculated in physics.
Power is the rate of energy consumed during the work.
Answer:
He needs 1.53 seconds to stop the car.
Explanation:
Let the mass of the car is 1500 kg
Speed of the car, v = 20.5 m/s
He will not push the car with a force greater than, 
The impulse delivered to the object is given by the change in momentum as :

So, he needs 1.53 seconds to stop the car. Hence, this is the required solution.
N₂ / N₁ = 13.3
A transformer is a device that changes the voltage in the primary, causing a voltage to be induced in the secondary. The expression for this voltage ratio is
ΔV₂ = N₂ /N₁ ΔV₁
where N is the number of windings on each side and V2 and V1 are the voltages in the secondary and primary, respectively.
They state that the primary voltage in this instance is 9.0 V and the secondary voltage is 120 V.
ΔV₂ /ΔV₁ = N₂ / N₁
N₂ / N₁ = 120/9
N₂ / N₁ = 13.3
Learn more about voltage here brainly.com/question/16774947
#SPJ4.
A 9.0-V battery (with nonzero resistance) and switch are connected in series across the primary coil of a transformer. The secondary coil is connected to a light bulb that operates on 120 V. Determine the ratio of the secondary to primary turns needed for the bell's transformer. Determine the ratio of the secondary to primary turns needed for the bells transformer. Ns/Np=?