Answer:
D. If a home were wired in series, every light and appliance would have to be turned on in order for any light or appliance to work.
Explanation:
In a series circuit, all the appliances are connected on the same branch of the circuit, one after the other. This means that the current flowing throught them is the same. However, this means also that if one of the appliance is turned off (so, its switch is open), that appliance breaks the circuit, so the current can no longer flow through the other appliances either.
On the contrary, when the appliances are connected in parallel, they are connected in different branches, so if one of them is switched off, the other branches continue working unaffacted by it.
My guess would be about 10 years because stars are hot balls of light that are reflections from years ago so it would most likely take awhile
Here As we can see the figure that the end of the rope is pulled by some force F
Now as we can see that Piano is connected by a pulley which is passing over the pulley so effectively net force on the piano upwards will be 2F as it is connected by 2 ropes by the pulley
Now for constant velocity of the piano we will say

since velocity is constant so acceleration must be ZERO
so here we have

as we know here that
mg = 1000 N
so we will have


so here force must be 500 N

Heat capacity of body 1 :

Heat capacity of body 2 :

it's given that, the the head capacities of both the objects are equal. I.e


Now, consider specific heat of composite body be s'
According to given relation :



[ since,
]




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Answer:
The initial velocity of the car is V1= 5.58 m/s = 20.12 km/h
Explanation:
m1= 1689 kg
v1= ?
m2= 2000kg
v2= 17 km/h = 4.72 m/s
by the conservation of quantity of movement :
m1*v1 = m2*v2
v1= m2*v2 / m1
v1= 5.58 m/s = 20.12 km/h