Answer:
The value of smaller resistor is 248 Ω.
Explanation:
Voltage divider circuit is used to convert a higher voltage to a smaller voltage with the help of resistors which are connected in parallel.
As shown in the circuit, Vs is the source voltage, R₁ and R₂ are the two resistors and V₀ is the output voltage.
Applying KVL in the circuit, the output voltage is given by :
According to the problem, R₂ = 310Ω , V₀ = 5 V and Vs = 9 V. Substitute these values in the above equation.
R₁ = 248Ω
Answer:
Part a)
Part b)
Explanation:
As we know that there is no external force on the system of two masses so here total momentum of the system will remains conserved
so we can say
Part b)
magnitude of the initial speed of A = 
magnitude of the initial speed of B = 
magnitude of final speed of A = 
magnitude of final speed of B = 
Now change in total kinetic energy is given as
The mechanical energy isn't conserved. Some energy is lost to friction.
Option A.
<h3><u>Explanation:</u></h3>
The mechanical energy is defined as the energy of a body which it achieves by virtue of its position and velocity. The mechanical energy are of two types - potential energy and kinetic energy. The potential energy is the energy of the body which it achieves by means of its relative position and is directly proportional to the height of the body from its relative plane. Whereas the kinetic energy of the body is achieved by virtue of its velocity and is directly proportional to the square of velocity of the body.
As the mountaineer is skiing down the slope of a mountain, the potential energy of the person is gradually changing into his kinetic energy. Had it been in an ideal situation, the potential energy lost would have been just equal to the kinetic energy gained by the person. But there's friction which opposes the speed of the body and reduces the velocity. Thus the kinetic energy will be lost to some extent and the energy won't be conserved.
A heat pump has a coefficient of performance of 7.05. If the heat pump absorbs 20 cal of heat from the cold outdoors in each cycle, find the heat expelled to the warm indoors. Answer in units of cal. I believe COP (heating mode) : 7.05 and COP = Qh/W Qc = 20 cal so I have to find Qh= ? cal I dont know an equation to put all this together? Please help, thank you.
The viscous force on an object moving through air is proportional to its velocity.
The only forces acting on an object when falling are air resistance and its weight itself. The weight acts vertically downwards whereas air resistance acts vertically upward.
Let F be the viscous force due to air molecules, B be buoyant force due to air and W be the weight of falling object. Initially, the velocity of falling object and hence the viscous force F is zero and the object is accelerated due to force
(W-B). Because of the acceleration the velocity increases and accordingly the viscous force also increases. At a certain instant, the viscous force becomes equal to W-B. The net force then becomes zero and the object falls with constant velocity. This constant velocity is called terminal velocity.
Thus at terminal velocity, air resistance and force of gravity becomes equal.
