 # Electric current problems with answers

Recent questions in Electric current linziboobeary1o8p 2022-05-08

### If a current of 4A passing through a circuit generates 16W of power, what is the resistance of the circuit? Carley Haley 2022-05-07

### Prove ${2}^{135}+{3}^{133}<{4}^{108}$ vulkanere64t6 2022-05-07

### The current flowing in a wire is inversely proportional to the resistance of the wire. If the current is 5 amperes (A) when the resistance is 24 ohms ($\mathrm{\Omega }$), for what resistance will the current be 8 amperes? kadetskihykw 2022-05-01

### The sides a,b,c of a $\mathrm{△}ABC$ are in GP whose common ratio is $\frac{2}{3}$ and the circumradius of the triangle is $6\sqrt{\frac{7}{209}}$.Find the longest side of the triangle.I used law of sines$\frac{a}{\mathrm{sin}A}=\frac{b}{\mathrm{sin}B}=\frac{c}{\mathrm{sin}C}=2R$I took $a=a,b=\frac{2}{3}a,c={\left(\frac{2}{3}\right)}^{2}a$which gives$\frac{\mathrm{sin}A}{\mathrm{sin}B}=\frac{\mathrm{sin}B}{\mathrm{sin}C}$I am stuck now,how to find the longest side a kulisamilhh 2022-04-25

### A circuit with a resistance of $6\mathrm{\Omega }$ has a fuse that melts at 8A. Can a voltage of 42V be applied to the circuit without blowing the fuse? Waylon Mcbride 2022-04-12

### The particle is falling down, and x is measured in down direction.${x}^{″}=g-k{v}^{4}\phantom{\rule{0ex}{0ex}}\phantom{\rule{thickmathspace}{0ex}}⟹\phantom{\rule{thickmathspace}{0ex}}\phantom{\rule{1em}{0ex}}v\frac{dv}{dx}=g-k{v}^{4}$Solving this I get$\frac{1}{4\sqrt{gk}}\mathrm{log}\left(\frac{\sqrt{k}{v}^{2}-\sqrt{g}}{\sqrt{k}{v}^{2}+\sqrt{g}}\right)=x+c$It is falling from rest, i.e x=0,v=0, using this initial condition I get $\mathrm{log}\left(-1\right)$ on the LHS. Is something wrong with the solution. I check that integral is correct. Jaime Coleman 2022-04-12

### Prove or Disprove that $|\frac{{e}^{2i\theta }-2{e}^{i\theta }-1}{{e}^{2i\theta }+2{e}^{i\theta }-1}|=1$This is a step in an attempt to solve a much larger problem, thus I'm fairly sure it's true but not absolutely sure. It looks like it should be simple but it's resisted all my attempts so far. llunallenaipg5r 2022-04-12

### What is the electric current produced when a voltage of 12V is applied to a circuit with a resistance of $55\mathrm{\Omega }$ ? Brooklynn Hubbard 2022-04-12

### A circuit with a resistance of $8\mathrm{\Omega }$ has a fuse with a capacity of 3A. Can a voltage of 36V be applied to the circuit without blowing the fuse? Jordon Haley 2022-04-07

### Ohm's law is represented by the equation $I=\frac{V}{R}$. How would the current change if the amount of resistance decreased and the voltage stayed the same? Justine Webster 2022-04-07

### What is the electric current produced when a voltage of 24V is applied to a circuit with a resistance of $40\mathrm{\Omega }$ ? zuzogiecwu 2022-04-07

### If a current of 5A passing through a circuit generates 450W of power, what is the resistance of the circuit? lasquiyas5loaa 2022-04-06

### How is the net resistance lesser than the least resistance when resistances are connected in parallel? The electrons will have to flow through one of the resistances, right? To me, it seems like the net resistance should be equal to the least resistance. Can someone please explain intuitively? (I know how the formula works) Regina Ewing 2022-04-06

### If the voltage doubles, what will happen to the current? Alisa Durham 2022-04-06

### A submarine of mass m is travelling at max power and has engines that deliver a force F at max power to the submarine. The water exerts a resistance force proportional to the square of the submarine's speed v.The submarine increases its speed from ${v}_{1}$ to ${v}_{2}$, show that the distance travelled in this period is $\frac{m}{2k}\mathrm{ln}\frac{F-k{v}_{1}^{2}}{F-k{v}_{2}^{2}}$ where k is a constant.I've found $\frac{dv}{dt}=\frac{1}{m}\left(F-k{v}^{2}\right)$ using $\sum F=ma$ but I am struggling to progress further using integration or the fact that $\frac{dv}{dt}=v\frac{dv}{dx}=\frac{d}{dx}\left(\frac{1}{2}{v}^{2}\right)=\frac{{d}^{2}x}{d{t}^{2}}$ which is how I've been taught to solve resisted motion questions. jubateee 2022-01-03

### A capacitor is charged to a potential of 12.0 V and is then connected to a voltmeter having an internal resistance of $3.40M\mathrm{\Omega }$. After a time of 4.00 s the voltmeter reads 3.0 V. What are (a) the capacitance and (b) the time constant of the circuit? PEEWSRIGWETRYqx 2021-12-16

### A hollow, conducting sphere with an outer radius of 0.250 m and an inner radius of 0.200 m has a uniform surface charge destiny of $+6.37×{10}^{-6}\frac{C}{{m}^{2}}$. A charge of $-0.500\mu C$ is now introduced at the center of the cavity inside the sphere. (a) What is the new carge density on the outside of the sphere? (b) Calculate the strength of the electric field just outside the sphere. (c) What is the electric flux through a spherical surface just inside the inner surface of the sphere? Baublysiz 2021-11-21

### An oil pump is drawing 44 kW of electric power while pumping oil with ρ= 860 kg/m^3 at a rate of 0.1 m^3/s. The inlet and outlet diameters of the piper are 8 cm and 12 cm, respectively. If the pressure rise of oil in the pump is measured to be 500 kPa and the motor efficiency is 90 percent, determine the mechanical efficiency of the pump. jazzcutie0h 2021-11-20 verskalksv 2021-11-07