Answer:
3A
Explanation:
Rtoal=R1+R2+R3=5+10+15=30
I=V/R 90/30
I=3
A small boy is playing with a ball on a stationary train. If he places the ball on the floor of the train, when the train starts moving the ball moves toward the back of the train. This happened due to inertia
An object at rest remains at rest, or if in motion, remains in motion unless a net external force acts on it .
When a train starts moving forward, the ball placed on the floor tends to fall backward is an example of inertia of rest. Due to the reason that the lower part of the ball is in contact with the surface and rest of the part is not . As the train starts moving, its lower part gets the motion as the floor starts moving but the upper part will remain as it is as it is not in contact with the floor , hence do not attain any motion due to the inertia of rest simultaneously i.e. it tends to remain at the same place.
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Answer:
effeciency n = = 49%
Explanation:
given data:
mass of aircraft 3250 kg
power P = 1500 hp = 1118549.81 watt
time = 12.5 min
h = 10 km = 10,000 m
v =85 km/h = 236.11 m/s
kinetic energy
kinetic energy 
gravitational energy 
total energy 
effeciency n = = 49%
