Recent content by ZxcvbnM2000

Thank you :)

Hello , i would to ask if it is possible for an INVERTING summing amplifier of three input voltages ( V1,V2,V3) to have some of them negative and some positive i.e V1>0 and V2<0 and V3<0 or any other combination. Thank you !

Okay so :Vc = E - e^(-t/T)*(E-Vc') so Vc = -20 -e^(-8/5.44)*(-20-11.33) = -12.8 V , Is that correct ?A friend of mine said that Vc = 11.33*e^(-8/12) -20*(1-e^(-8/5.44)) . He said that it's discharging through two resistors ... i am even more confused now !

Hmm , 20 volts ?But why is it a decay ? It is supposed to be charging , no ?

Homework Statement The circuit shown in Figure 5 contains two emfs of opposite polarity E1 = 40 V, and E2 = -20 V. The circuit also contains a switch, resistors R1 and R2, and a capacitor C.The capacitor is initially discharged. The switch is connected to position ‘a’ for a period of 8...

Thank you for your answers. So we can say that Vterminal = E - Ir ? so 4.9 = 5 - Ir <=> 0.1 =Ir so the voltage drop across the battery's internal resistance is 0.1 V so this either means that the voltmeter has zero resistance or they are in parallel.Right ? But if they are in parallel then...

Homework Statement A battery is known to have an emf of 5 V, but when a particular voltmeter is connected to it the reading is 4.9 V. With the voltmeter disconnected and a load resistance of 12 Ω connected to the battery, a current of 0.4 A is delivered. What is the resistance of the...

Thank you very much !

In elastic collisions : Momentum is conserved Energy Is conserved In inelastic collisions: Momentum Is conserved Energy is not conserved Just to be more clear :P

In elastic collisions energy is also conserved , so you can set up one more equation .

Homework Statement A capacitor of capacitance 9 μF is fully charged from a 200 V dc supply. The capacitor is now disconnected from the supply and connected in parallel with an uncharged 3 μF capacitor. Once the 3 μF capacitor is fully charged, it is removed and discharged. a) What charge...

Hmm dL=Iω=J*R=MVR but i realized that V=ωR is not valid , why is that ?

Actually no :S

ΔL=IΔω but since it was stationary at first then ΔL=Iω It seems to be simple but i still can't understand how to relate these two :S

Homework Statement A uniform solid sphere has radius R and mass M. It is initially at rest but is free to move, floating in space with nothing touching it. It suddenly receives an impulse J at a tangent to its surface. As a function of R, M and J, find formulae for: (a) the linear...